Bad Ecu Ground

The ground is a major part of the battery's charging system, so assuming that you're getting proper voltage output from the alternator wire, and the battery isn't hashed, then you may be looking at a bad ground wire. ECM Repair/Rebuild All of our R&R services are conducted in house by our certified technicians. DO NOT use test lamp! If no 5V is found on pin #3, ECU is defective. One other thing is that one of my engine grounds was not well connected, something my wife pointed out to me to say there was something sparking. Before you commit to spending this kind of money get a mechanic to do the diagnostic job first instead of just guessing. 78-1044F for 2005-2006 Ford Escape and Mercury Mariner 2WD 3. A mechanical problem that a technician fails to recognize (or recognizes but fails to fix properly) is often blamed on the ECM. The bottom arrow shows the ignition control module. These devices monitor the fuel, air and electrical aspects of a Chevrolet engine to ensure optimal engine performance. EFI" on the diagram below. The ECU is grounded to the engine also. Where is the ecu ground on a 2002 4sl rodeo. Resistance should be less than 25 Ohms if the system is connected properly. so i called my bro. With a test lead ground X3 pin 23 (pin 46 for CEC modules) and retest for engine crank. With a premium-quality Engine Control Module, such ease of control is well within your reach. In my honda book it says code 0= bad ecu. The engine may still crank, but it will not be able to start without the vital inputs from the computer. The ignition module and the EEC-IV are not so likely. That will severely affect the car's performance. 12114: (if this code comes up you should have ecu replaced and blank off egr). In the case of coolant temperature, it means that as injector duty cycle increases, the voltage seen by the ECU on the coolant temperature input. vodka, Mar 17, 2017 #10. 2- The ECU sounds out positive voltage to the stick coil at the timing dictated by the pulsar coil. The ECM, or electronic control module, is the computer responsible for controlling all of the engine management functions. The generic trouble code P2509 power input signal intermittent refers to an engine with an intermittent electrical signal to the Electronic Control Module (ECM) otherwise also known as a PCM or Powertrain Control Module. ECU issues/ground strap. As far as the ground is concerned on the '03, follow the battery negative cable. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. The check engine light came on, and I took it to the dealer to get the diagnostics on it, and they said it was a bad ECM ground, and that it needed to be cleaned off, would take about an hour and 250. Voltage supplies should be checked and verified. The #5 ground wire is a yellow-green wire. A constant bad ground -- resulting from a frayed or damaged cable -- will create resistance in the circuit, which will deprive the headlights of power and cause them to dim. I have swapped injectors from cylinder to cylinder prob stayed a cylinder #3. DTC – Diagnostic Trouble Codes ECM – Electronic Control Module. Wire in link management ECUs, Plug in ECUs, accessories and much more. I DO have the 12V from the orange wire(pin 5), which is hot all the time from ECMb fuse. But overall, it's not practicle to drive. the ecm relay may allow silicon vapor to form and, over time, the silicon evaporates from the diode molding which causes silicon oxide to develop on the ecm relay contact due to arcing. Chrysler Electronic Ignition The other important component of the electronic ignition system is the ballast resistor. 10 B ECM Ground GND-I The ECU provided ground goes to various sensors. 85 Corvette Ground Wiring Diagram from bad boy buggy ecm relay , source:20. Ecu Transit. Followers 1. So many myths, many of them downright crazy, make it nearly impossible to make clear-headed and smart decisions for your customers. It would be a great help. Ecm Performance offers custom Engine Control Module (ECM) programming & Diesel Particulate Filter (DPF) Solutions for Cummins ISB 6. If the ECU relay is suspect, then it should be removed and either repaired or replaced. ) O2 sensor wire - Sensor pigtail may be mispositioned and contacting the exhaust manifold. Link ECU design & manufacture engine control units that are available worldwide. So i decided to google the issue, and yup seems to happen to all 2000 Chevy SUV's Came across your post and decided to check all my wiring to crank sensor, power steering pressure sensor, and ground location. A bad ground can cause noise in an audio system, make electric fuel pumps run hot or produce low pressure, and make electronic engine controls do weird things. A good way to test grounds is through a voltage drop test. However, purchasing a new engine control unit is expensive. But if you just put the ground from the alt to the chassis, should not have harmed anything. The pump is 4 AMPS running, if it hits about 10 amps the ECU goes quite MAD! The pump can go bad and become this huge noise generator. The contacts of the relay will apply battery voltage from engine ECM 40 amp fuse (9254) to ECM connector (6007) pins 21, 22, and 41. Re: Issue with engine shutting down while driving. The bad earth/ground can be traced to an essential ground strap on the front upper transmission bolt. DTC P0122: APP SENSOR SIGNAL VOLTAGE TOO LOW Monitor & Set Conditions Accelerator Pedal Position Sensor (APPS) voltage is monitored when the engine is running. I bought it used off Ebay so it's possible but I wanted to know if anyone else has had this problem. It may not sound much, but bad grounds cause all sorts of problems, few of which are actually related to dc voltage - current loops, emc pickup, frying ECU's (oh yes indeed), etc, etc The ECU doesn't adjust for economy, it adjusts for the best drive. Also, assuming that an ECU is faulty because of no CAN communications, where the CAN gateway may be faulty or another ECU may "hang" the CAN bus, can be misleading. If you need to fix or replace it, you better be able to identify it first. Bad TPS Ground Voltage Drop testing sensor grounds. As far as the ground is concerned on the '03, follow the battery negative cable. Depending on what version Duramax you have, simply snip off the other wire somewhere close to the switch. 2- The ECU sounds out positive voltage to the stick coil at the timing dictated by the pulsar coil. There are three other wires that connect the ICM to the ECM besides the bypass wire (which is tan w/ black stripe). If something has automated features in it, then there's an ECU somewhere to control it. Ok, so I did a bit more testing today. The Bulls may have played the best game so far this season. Their flatrate express service guarantees the ECU by 3 P. We went through to try and verify all the grounds to the ECM's. Renix engines are notorious for having bad / faulty ground connections as a result of age and not so great design in the connectors. - Check for continuity to ground on the ground side. Where is the ecu ground on a 2002 4sl rodeo. MIL "ON" WITH DTC U1000 OR U1010 STORED IN ENGINE CONTROL UNIT This bulletin has been amended. If bad, continue: Disconnect engine bay connector for TDC sender. I found a link on the internet with a simple analog Voltmeter test that can be performed at home on Chrysler products, but I'm not getting ANY of the results they specify to tell whether the ECM is good or bad. It's a bummer, I will not be back. It may not sound much, but bad grounds cause all sorts of problems, few of which are actually related to dc voltage - current loops, emc pickup, frying ECU's (oh yes indeed), etc, etc The ECU doesn't adjust for economy, it adjusts for the best drive. The red wire does show as ground when I switch on the ignition for a few seconds, so that is fine. Could this be a bad ecm but Im wondering if its a bad ground, or will the box (ECU) need replaced?. Voltage supplies should be checked and verified. Both show battery voltage and ground just the same. Grounding to the engine block is usually better than grounding to the frame. Bad ground to ECU help me wire this please Long story short an O2 sensor CEL led me to find out that i have a bad ground on a7 and a15 on the ecu. ECM vs PCM: What’s the Difference? (Updated) Whether you’re looking to tune your car or you want to understand why your car isn’t running right, you’ll have to learn about on-board computers. Both show battery voltage and ground just the same. I didn’t like the literature on the two wires going from the Fuel Pump Control ECU to the ECM. I'm confused if maybe It could be my aftermarket alarm installed which is having some weird behavior problems. Now if someone can tell how I start looking for this ground or in what area I should start looking. If pin 22 circuit is shorted to ground internally,that would cause the fuel pump to run continuously. If you want to request help or have a query regarding the modifications on this site you need to register and then post a private thread in the Help Desk. In analog design, the relationship of a signal to ground is of fundamental concern (and can create issues in digital designs, too. Some codes pertain to more than one system but there will be only one of the systems on the vehicle. Next stop is CR48 But im not hearing a relay click Is CR48 the relay in the contoel box with the ECM module in the battery compartment?. If it is faulty, it may be intermittent. The GM TBI system I'm installing uses an 8-pin ignition module. The ECU needs to be programmed with the current Vin of the vehicle as well as the odometer. Even when I do Wide band hook ups the ground is directly on the head. but i have spark and still wont start. Same thing happened on my '88. It was driven to the customer's own local garage, where they carried out the usual checks, and was starting to look like the ECM had failed. When installing a Holley or any EFI system to your vehicle, it's imperative to have a proper ground and voltage for the system. I know that O2 sensors use a controlled ground in able to sense the heater current as an example. #9 pin is ECM ground. I figure I have a bad maf b/c when I unplug it, the idling stays the same. That would probably be the same as the S for the ecm ground, which is probably under the seat somewhere. Any Solenoid (VSV) or ISC connected to ECU that is shorted. 3 Trouble light shining Parts are bad According to the. However, purchasing a new engine control unit is expensive. The shematic is very puzzling as it shows the hot side of the circuit going directly to ground through that relay until the relay energizes and connects the ground. Grounding issues. wires that feed the fuse panel and ECM, there are several, check fuses. High ohms/open = burnt out clutch, bad wire; low ohms = either good clutch or possibly shorted wire. The article I wrote on how to locate a short-to-ground using a lab scope (November 2015) did not cover how to diagnose a computer's 5V reference circuit that's shorted to ground. I assume this means that I have a bad ground somewhere. Research the Used 2005 Pontiac Grand Am with our expert reviews and ratings. I'm still not sure if a bad ground is to blame. Check your Fuses for blown fuses. The relay would have to be closed to get the zero ohms I was looking for there. I also revised my earlier post, for any reason 2 sentences got lost. Through process of elimination you will determine if the ECU has failed. If you disconnect the battery and the car conks out, you don't know if it conked out due to insufficient alternator current, or whether the resulting transients caused your ECU (the car's computer, which controls fuel mixture, timing, and much more) to spit out bad data, shutting down the car. Burning electrical smell was coming from the engine while trying to restart. The ground bolts were specifically used for the back of the heads. The higher current items like the fuel pump is handled by the pump relay controlled by the ECU by providing a ground to the relay's control circuit. Description Chevrolet ECM Repair Electronic Control Module Repair. Once again corrosion or breaks in the internal wiring in the harness can cause a short in the ECM or corrosion can enter the ECM through the wiring harness. The inner 2 wires I don't know how to test to see if the signal is getting to the ecm. I did a cursory search yesterday looking for frayed or broken wires, lose grounds, etc. Hoping to be enlightened! B20 hestitation. Grounds checked good up on the intake by the engine pull tab and at the core support. The car suddenly developed a misfire and never recovered. Since it is a dedicated ground, it passes through the computer on its way to the computer main power ground that terminates at the battery pigtail ground. But that’s probably ok. The original ground comes from two engine grounding points located at the topside of the upper intake manifold. 0v, checked with pressure/vac and the signal from the sensor goes to about 2. The power wires all had charging system voltage and the ground was ok at 0. The check engine light came on, and I took it to the dealer to get the diagnostics on it, and they said it was a bad ECM ground, and that it needed to be cleaned off, would take about an hour and 250. Checking the Fuel Pump relay, I find that the trigger from the computer is only giving 5. Hey guys, so my car has been driving great for months now. The connection is made internal to the ECU. spark passes from the center electrode to the ground electrode and in the other plug the discharge is in the opposite direction, i. RE: ecu replaced ! problem!!! IP: Logged Message: Your bad pcm did not show you the bad sensors now you can see them What year the o2 sensors 4 wires 1 ground 2 sensor ground to comp 3 ASD voltage 4 sensor signal sensor ground to comp is the same for all sensors to comp, TPS, MAP,IAT o2 all come back to same ground wire on comp. I went ahead and attached the ground to the upper starter bolt. Some codes pertain to more than one system but there will be only one of the systems on the vehicle. However, the A20 ground to the block was not grounded back to battery. I have heard that engine cut out on hard corners can be created by a bad ground to the ECU. ) However, "ground" as a concept can be confusing as it relates to three different situations: chassis ground, signal ground, or earth ground. 90 shipping. We professionally repair your Mercury PCM or Mercury ECM for models Mariner, Milan and Sable. ECM-PCM's ground goes to the body. They will do what you said above. I also have a 98 ecu which is the original one from the car but i'm hessitant to put it back in especially since I can't even get the thing open, so if anyone has any hints on how to open a 98 ecu the one with the black box i'd really appreciate it. It could happen at any time: You are driving on the highway, moving. indicate a shorted actuator to ground, but the output driver of the ECU providing the DTC may be the actual problem. Please discard all paper copies of NTB98-008a. I narrowed it down to the red/blue wire on the compressor relay. I found a link on the internet with a simple analog Voltmeter test that can be performed at home on Chrysler products, but I'm not getting ANY of the results they specify to tell whether the ECM is good or bad. We’ll be dissecting each plug and it’s functions and wire values as well as wiring color diagram as well. They are fairly common. 01uf looked bad the. Connect the test light's ground clip to a good ground and touch it to a point where you believe that there is 12v. my signal is showing ground. Manually fired the injectors by groundi. This method should only be used if all other attemts to connect to the module fail. Before ordering another ECU make sure you have +12v on ECU pin 20 when key is on and pin 46 all the time or ECU will never power-up. Electronic Fuel Injection System The Electronic Control Unit is an integral. 10 B ECM Ground GND-I The ECU provided ground goes to various sensors. The factory has them grounded through the steering column support which is bolted to the chassis and over time the bolts get rusted and it loses its ground. Check all electrical connections. We can save you the time and money by testing your ECU DME before spending on costly diagnostic labor and sensors. Haven't checked the wiring yet, but anyone seen this, or could the ecu be bad?. With clip uppermost, check for continuity between the right contact and ECU connector pin 13. when you crank and start your Ford vehicle: The throttle position sensor gets 5 Volts and Ground from the ECM. The terms ECM and PCM are often used interchangeably when referring to engine electronics, but there is a difference. I am thinking that it is good since none of my symptoms changed when I swapped to the remanned from the old. I found a link on the internet with a simple analog Voltmeter test that can be performed at home on Chrysler products, but I'm not getting ANY of the results they specify to tell whether the ECM is good or bad. The check engine light came on, and I took it to the dealer to get the diagnostics on it, and they said it was a bad ECM ground, and that it needed to be cleaned off, would take about an hour and 250. Missing at idle is usually ignition and the culprits are the spark plugs, wires and coils. Check the wiring and FYI the bad vacuum or failure of sufficient vacuum is what causes an ECU driver to be over worked and melt down as a result of trying to run the pump for extended amounts of time. The story, in short version, is that my 1993 Ranger had gradually developed a problem where it would buck, and pop, and lose power. Learn about this problem, why it occurs, and how to fix it. So instead I had him jump power and ground to the fuel pump itself from connector B. If not, check the wiring diagram to find where the wire is grounded. In such a scenario, the ECU will sense the drop in engine vacuum first and then using other sensors data will decide if more fuel is required. BMW 3 Series ECM ECU DME Repair & Return Service All Years. The 2009/2010 Touring bikes require a ground wire from the XiED's. DTC may be stored if low voltage is detected on APPS signal circuit or low voltage is detected between Engine Control Module (ECM) and Powertrain Control Module (PCM). Your going to have to drop the glove box and you will see it to the right of the blower motor. If the ECM fails completely, it will leave the vehicle without engine management control, and will not start or run as a result. anyone ever have a bad ecu on an apex if so how did it act sometimes the lights dow't work. 95, UPS quoted me 66 for overnight and FedEx was 60 as well. On very few systems, the operation is actually the opposite; in which case the injectors are supplied a constant ground and the ECM provides the positive pulse. 9 to 1 Volts. If there was a problem with your wiring harness, power, sensors excessive heat, etc. The signal is not constant and within parameters with the ignition key turned off. I tightened it and everything seemed to be working. If you probe the B/Y wire between the fuel pump relay and the ECU, then connect your other lead to ground, there should be zero voltage between them when the fuel pump should be on, and 12V when the fuel pump should be on. To condemn the ECU, you need to verify everything else is good. No ICV vibration, but I can ground those two pins at ECU and get movement. I took it into the local dealership and they said the ECM is bad and I need a new one to the tune of $800. Electronic Fuel Injection System The Electronic Control Unit is an integral. Profitec/ECM CEO Michael Hauck also told DCN he appreciates the wisdom and efficiency of older designs. The switch also includes a ground eyelet that can be fastened under the switch on a grounded metal surface. Check distributor and ignition system. Engine hesitation during acceleration: a bad throttle position sensor will make very hard for the ECU incrementing the necessary amount of fuel during sudden acceleration. DTC – Diagnostic Trouble Codes ECM – Electronic Control Module. Such a ground lead is attached to the engine block or chassis and feeds an ECM O2 ground pin only. The ECU itself uses a 3 amp fuse so it cannot pull enough current to pull the battery voltage down that far. The 2003 Cavalier does not have a AF ECU therefore corrosion issues don't apply to your vehicle. If the PCM is damaged, especially by water, assume that it will need to be replaced. This is known as Electro-Motive Force (EMF) This deflection in the voltage on the falling edge is where a diode in the ecu is regulating the rate current diminishes from the circuit. It is the central control unit of most vehicles and controls a variety of functions, such as electrical system power distribution, emissions, ignition, and fuel systems. Again this is caused by exposure to the elements. OK, that seems to eliminate bad fuel as a contributor. The injectors (3, 4, 5, 6, 8, 10, 12, or 16 of them) are operated by individual transistors inside the ECU that control the ground side. That doesn't mean that I dont have an exposed wire in there that is shorting occationally. The ECM is notified by oxygen sensors if the engine is running lean (little fuel and too much oxygen) or rich (so much fuel and less oxygen). **The internal battery in DDEC IV ecms is not the only part that fails over time. I will look for a few more though. The O2 circuit is then grounded through the inside of the ECM electronic board by this ground wire. A failing camshaft position sensor (CMP sensor) can produce a confusing range of problems, depending on the way it fails and the model of the car: An intermittent or complete CMP sensor failure while on the road could be dangerous. wires that feed the fuse panel and ECM, there are several, check fuses. I go back yesterday and they tell me that the ECU was bad. 1986 - 1987 Ford Mustang 5. The ECM, or electronic control module, is the computer responsible for controlling all of the engine management functions. In terms of actual wiring, you want to use at least 14 gauge wire for the body ground (see our ground kit for more info). Control the bad plays with a young quarterback and let him go out and play and play his game. Unplug the ECM / PCM connector and get a pinout schema of the ECM connector. If bad, continue: Disconnect engine bay connector for TDC sender. The pin chart showed 0-3v on one wire, and less than 1. Even when I do Wide band hook ups the ground is directly on the head. (On is *not* start!) The "check engine" light will flash. That would probably be the same as the S for the ecm ground, which is probably under the seat somewhere. I got a code 12 : ecm motor driver circuit. Not real familiar with the traction control system, but I know it will cut injector out at times. Next stop is CR48 But im not hearing a relay click Is CR48 the relay in the contoel box with the ECM module in the battery compartment?. The gauges not responding is the ECU just not putting the data on the bus which could be a short, like the fan, or a bad gorund and it went to fail over mode and did not fully come on line. The ECM, or electronic control module, is the computer responsible for controlling all of the engine management functions. (Message edited by greg_e on September 17, 2015). If you are using a 12V power you should see 12V on the meter. I go back yesterday and they tell me that the ECU was bad. Many think that as long as the accessory's ground wire is touching some part of the vehicle, it is grounded. three hours later they Dx a bad ECU. I doubt all 4 signal wires are grounded outside the ECU. Check all electrical connections. Volkswagen Jetta Difficult to Diagnose Electrical Issues Are Typically Due to Ground Issues - 195 reports. If you're in the rear of the vehicle, you can touch the main power wire where it goes into the distribution block. DME ECU ground signal missing Continuity test performed from wire 85 relay to pin connector 27 of DME is good. In-shop rebuilding is impractical and often results in a short-lived repair. Hello everyone, my name is Anthony. If the ECU is suspected as a bad part, you need to use a scan tool such as a VAG com to attempt to communicate with the ECU. However, not all ECM motors run at variable speeds and selection depends heavily upon application specifications. A bad driver in the ECU, but since you said it's a MEFI then 4 out of 8 would still fire, unless you actually killed the ECU. You will have hard starting, low power and drivability problems. Stairway Alcove Ground Floor. The bad earth/ground can be traced to an essential ground strap on the front upper transmission bolt. Thought maybe that relay, which I have already tested over and over, was just bad enough to screw with things. to remain open against spring & fuel pressure The ECU removes the ground supply, this causes the magnetic field which has built up in the windings to be released. If you have good continuity on all of those pins, then you're looking at either bad or intermittent power to the ECU (bad ground, probably - it might still run the engine under these circumstances), or a bad. With a premium-quality Engine Control Module, such ease of control is well within your reach. It may not sound much, but bad grounds cause all sorts of problems, few of which are actually related to dc voltage - current loops, emc pickup, frying ECU's (oh yes indeed), etc, etc The ECU doesn't adjust for economy, it adjusts for the best drive. Im referring to the solution of the following thread. Yes I agree , my first check was the battery box all the fuses and checking pins then checked voltage at ecm relay , --I just checked power and ground to connector 6020 (at the ecm ) from the clean power circuit found had battery voltage and ground at all pins that were fed by clean power circuit. Where is the ecu ground on a 2002 4sl rodeo. when i did the diagnostic check the check engine light came on but didn't blink so thats a code 0 right. With K-Series engines, especially with engine swaps or situations where the intake manifold has been removed, it is important to ensure there is a good ground connection between the ECU and the cylinder head / engine block. NOTE: When you see "is/was" listed for a code: For a HARD fault code the sensor IS out of range right now. and lastly the NEG to NEG ground of the. 5 = 5V Signal/Ground (confused on this one - but on a red wire - XJRS) 7 = Ground (black wire XJRS) 9 = TX/RX 0. This article will teach you how to replace the ECU, ECS and digital climate control capacitors in a Mitsubishi 3000GT/GTO and Dodge Stealth. ok, so here's the full scoop, my 95 gsr started sputtering and having ridiculous, erratic tach movements, losing power, etc. Top 5 Symptoms of a Bad Negative Battery Cable. With the engine running wiggle and tug at the wires from the Ignition Coil to the ICM and also the other connector on the coil. Recently, I found out for sure that my 1996 Toyota Camry DX, 4 cylinder, Automatic had a bad ECM to replace. ECU - Engine Control Unit ECM - Engine Control Module PCM - Powertrain Control Module EBX - Engine Brain Box The ECU works in concert with the sensors on your engine and accordingly controls the supply of fuel and spark for your cars fuel injection system. If you have access to a Fluke 1587 or similar insulation resistance tester, that would be very useful when testing for opens or shorts to ground or shorts between wires under load. Grounding a gauge to the radio is usually bad- ground offset can vary with volume. If you do not see your particular vehicle listed, please call us at 800-547-2049 to discuss repairing your module. Our turnaround time averages between 2 to 4 business days. In my honda book it says code 0= bad ecu. Van stopped on road and would not restart. when i did the diagnostic check the check engine light came on but didn't blink so thats a code 0 right. ECM 5v pin to ground = Steady 5V OK This customer drives his taxi with a defective battery with a bad cell. The ECU is located behind the glove box. Common areas that cause failures are: poor grounds and powers, bad wiring, shorted solenoids/relays, or misdiagnosis by the installer. ► Show Full Signature. However the one thing it can't do is stop the car from running at all. Do you here the ig realy turn on with key ? and feul pump realy should turn on and cycle have seen the odd ig realy go bad but whould have no check engine light. The 1st relay provides power to the DME. If the connections are good and free of corrosion, you should check the bypass wire for an open circuit or short to ground. A Worldwide Parts Services Distribution Network. Check out our other i-VTEC related guides here. In case the sensor is faulty, it might be intermittent. The Injector Driver Module inside my computer with ECU code YDH1 has decided that it does not want to work properly anymore, and keeps giving me Check Engine Code P0206, Cylinder 6 Open Injector Circuit. This is independent of the ECM-only the ground wire goes into the ECM, to be internally grounded to pulse the injector. Many ground wires bolt to the engine, and sometimes mechanics will forget to re-connect the ground wire after doing a repair. I figure I have a bad maf b/c when I unplug it, the idling stays the same. February, 2012 My son and I have had a terrible time with our Ford Ranger. Faulty Engine Control Module (ECM) Engine Control Module (ECM) harness power supply circuit is open or shorted Engine Control Module (ECM) harness ground supply circuit is open or shorted. How to tell if your car has a bad ECU? A shop can check for good voltage across the battery and a good engine ground, which is a logical place to start. if your ecm is bad, first off the car won't start, your fuel pump won't work, no spark, basically everything shuts down Ok the above can be symptoms of a bad ECM, But that's not the only answer. Common areas that cause failures are: poor grounds and powers, bad wiring, shorted solenoids/relays, or misdiagnosis by the installer. Dealers and repair shops deal with these problems by what we call the shotgun approach (fixing something by replacing many things or one big thing). Resistance should be less than 25 Ohms if the system is connected properly. In the case of coolant temperature, it means that as injector duty cycle increases, the voltage seen by the ECU on the coolant temperature input. I have found a replacement second-hand ECU for sale locally but the label is red and the number is 0261200413- also from an automatic 525i saloon - probably built in '92. 5 volts of battery voltage. ECU Women's Physicians. MIL "ON" WITH DTC U1000 OR U1010 STORED IN ENGINE CONTROL UNIT This bulletin has been amended. What Are the Symptoms of a Bad PCM? The engine control module monitors the sensors found on the motor while the power train control module handles the drive train. Hello, I've posted this call for help on the ClubTouareg forum, but figured that I would get some helpful input from here as well. The end result might be the same -- you can drive your car again, after all -- but engine control modules and units do sometimes go bad, and they aren't really designed to be repaired -- at least, not by the owner or by an average mechanic. A bad mass air flow sensor will make very hard for the ECU incrementing the necessary amount of fuel during sudden acceleration. Bad ICM Bad Pick Up Coil Bad Ignition Coil to ICM cable Bad Ignition Coi. I went ahead and attached the ground to the upper starter bolt. Or in other words, my orignal pcm is fine and I wasted my money by partially "shotgunning" it as bad. I still had both ECMs, but neither would work. If the ECU is suspected as a bad part, you need to use a scan tool such as a VAG com to attempt to communicate with the ECU. You will have to dig around, move some wires and a few things out of your way to get to this. The original ground comes from two engine grounding points located at the topside of the upper intake manifold. Without this, the ECU tends to earth/ground elsewhere, causing a specific trace to burn out on the circuit board and killing the ECU. Is there a difference between manual and automatic transmission for the ecu?. Missing at idle is usually ignition and the culprits are the spark plugs, wires and coils. Maybe the ECU ground is not all that good. Would indicate it might be radiating? The ECU coil drivers pull the coils down with high current transistors. It’s got nothing to do with welding on the ground wire going to the ECU. Voltage supplies should be checked and verified. It works by using 2 probes to send a current through the circuit and measuring how much resistance, in ohms, that. If this ground is bad, none of the sensors mentioned will work properly. With the engine running wiggle and tug at the wires from the Ignition Coil to the ICM and also the other connector on the coil. spark passes from the center electrode to the ground electrode and in the other plug the discharge is in the opposite direction, i. Haven't checked the wiring yet, but anyone seen this, or could the ecu be bad?. Grounds checked good up on the intake by the engine pull tab and at the core support. People said i could have a loose wire/connector or a bad ground. The bad news? The Monarchs are allowing 89. •Determine if the source (battery +) or ground side of that section of the circuit is bad by the following: - Check for available voltage on the source side. - Clean/re-tighten negative battery cable body connection and battery post connection. Even the initial premise was wrong. Otherwise, look under the seat, in front of the battery and ECU and to the right of the Proportional Control Valve (PCV) for the brakes. Under all this you will find a 10mm bolt with another ground eyelet under it (see pic to right). Is air leaking into air induction system? Repair air leak. Swap it out yourself before you spend 2k! also check those relays, fuses and maybe fuel pump. it worked well in the warm weather tho. I really need to replace my battery ground cable one of these days.