How to fix no distributor reference pulse. 3 TBI Vin Z.
How to fix no distributor reference pulse. dropbox Jun 21, 2013 · I've determined the ECM is not receiving a distributor reference pulse from the newly installed Caldone distributor. 3 12's says all's well in ECM code land. What does this mean and how do you fix it? The Oct 3, 2023 · Using extension leads from injector connector to injector terminals I remove the injector, sat in cab with door closed, cranked, no pulsing. Trouble Code 12 is a special case code that is not logged into the ECM's Non-Volatile Memory (NVM) when detected. Mar 11, 2013 · Code 41 says that there are no distributor references pulses to the ECM at a specified engine vacuum. Dec 19, 2010 · okay, sorry my question is kinda lame. The distributor reference pulse is the basis for the timing and grounding of the coil. Jun 12, 2018 · C3 Tech/Performance - 1982 Corvette-Code 12 Problem - Hi, I am picking up a code 12 when check engine light is on. Engine code 12 indicates no distributor reference pulse, often caused by a faulty ignition pickup coil inside the distributor. After replacing the distributor the engine started right up but shut Sep 3, 2013 · GM Trouble Code 12 is a special-case code that is not logged into the ECM's Non-Volatile Memory (NVM) when detected. k do i find the obd-I connection on my 1987 chevy astro?!?! i've been looking all over the place =P thanks for any helping words=) ps: nice list! For 1995-previous model year EFI-equipped GM vehicles. 6 - Code 12 - No Distributor Reference Pulses Jump to Latest 4. 13. Oct 21, 2009 · All of the information you need to diagnose a no-start problem caused by the ignition module, or the ignition coil, or the distributor pickup coil. Dec 25, 2016 · ^^ Common failure item. The fact it sees no ign reference pulses is due to the engine not being cranked, or running. 3 TBI Vin Z. How can I fix this code? Jan 22, 2012 · Turn your ignition key on with engine off and the codes should start to blink. When cranking the engine over to start it, a reference pulse is generated by the pickup coil inside the distributor or the crank sensor in the block and is sent to the ignition module. The car still turns over but will not start running. Both injectors acted the same. Diagnostic manual comes with: Jan 8, 2011 · GM OBD-1 Diagnostic Trouble CodesFor 1995-previous model year EFI-equipped GM vehicles. DTC - 12 No distributor reference pulse (diagnostic test active)DTC - 13 Oxygen sensor circuit open or no activityDTC - 13 Left bank O2 sensor . This step checks for a poor connection at the EST 4 wire connector as being the source of no distributor reference pulse. Will start and run Sep 25, 2015 · OBD Code 12 - No Distributor Reference Pulse (Diagnostic Test Active) The Engine Control Module-ECM uses the distributor reference pulse to calculate the engine speed. 14. Using the 5v Reference Circuit as a Guide to No Start Diagnostics! #5vRef #autotechtraining Using the 5V Reference Circuit to Troubleshoot a No Start No COM w/ PCM Nov 16, 2012 · 12. . Check the distributor cap, rotor, and ignition module for wear or damage. Dec 20, 2012 · No change. Hasn't started since. Replace the O2 sensor. The PCM uses these two reference pulses to determine individual ignition spark timing for each cylinder. Check for corrosion, connector terminals not fully seated, or Jun 29, 2022 · No reference pulses (Code 12) might be a failed pickup coil (engine won't run) or a failed ignition module (engine probably won't run) a failed wire harness between ignition module and computer (engine won't run right) or a failed computer (engine won't run right). Check the electronic components of the dizzy. Suddenly coughed and died. Learn about GM OBD Trouble Code 12, including symptoms, causes related to distributor reference pulse issues, and troubleshooting tips on RepairPal. Injectors are not getting any commands from the computer. Jun 18, 2024 · Encountering the GM OBD1 code 12 can often signify that the engine computer, commonly referred to as the Electronic Control Module (ECM), is not receiving a signal from the distributor when the engine is cranking. com. Injectors are not pulsing. This code 12 means the diagnostic system is normal and will repeat itself continuously if there are no trouble codes. Looking at a wiring schematic for the '88 'Vette, please explain to me how you have spark, but "no distributor reference" please. The ECM will not send injector pulse without a distributor reference signal. Otherwise, code 12 will flash 3 times before flashing the fault codes. Fuel pressure is good, when I ground each injector I get a good cone of fuel spray. What does this mean? Does it mean the ignition module could be bad? Please help me out, Im going bald from pulling my hair out! Code Description Code 12 No distributor reference pulse (diagnostic test active) Code 13 Oxygen sensor circuit open or no When the ignition is "ON" and the ECM detects no ignition reference pulses coming from the ignition module, it illuminates the Service Engine Soon lamp. I do have 12v on one side of each injector clip. 8K views 16 replies 5 participants last post by caveman May 19, 2009 mattfromtelevision Discussion starter I put a new ignition coil, new control module and rotor. May 10, 2009 · 2. CODE 12 - No Distributor Pulses. Got good spark at the plugs. CIRCUIT DESCRIPTION The distributor ignition system provides two timing inputs to the Powertrain Control Module (PCM) , high resolution signal (360 pulses per crankshaft revolution) and low resolution signal (4 pulses per crankshaft revolution). Jun 11, 2019 · 1995 S10 4. Here is the reference material that i used to determine this: Opti-Spark Oscilloscope Pattern - CorvetteForum - Chevrolet Corvette Forum Discussion https://www. When the ECM detects no ignition reference pulses from the ignition module when the ignition is in the 'ON' position, it illuminates the Check Engine Lamp (CEL), but does not log this code as it would other codes. Diagnostics Entered- Normal Code, with ignition on and engine off, indicates no distributor reference pulse to ECM. NOTE: Some codes not supported on all models, consult your specific vehicle's service manual for the correct trouble code list and description for your application. My labeled low resolution is based on the varying pulses that indicate position. Still have spark but no injector pulse, still have DTC 1361. Below are the OBD DTC's for 1995 Jan 4, 2009 · Retrieving and Deciphering GM Computer Command Control Trouble Codes. where the f. Oxygen Sensor Circuit, check for a sticking or mis-adjusted TPS, check wiring and connectors for the O2 sensor. With no injector pulse and no ICM timing pulse it seems like the PCM is not getting some kind of input signal but what can I be missing? The crank position sensor is the common ground but it seems to be working properly. All codes should start with code 12 which is one long flash followed by 2 short flashes. I'm getting a E012 code mean no distributor signal. When the ignition is ON and the ECM detects no ignition reference pulses coming from the ignition module, it illuminates the Service Engine Soon lamp. This code could set with the key "ON", engine "Not Running" if the MAP or VAC sensor was defective by indicating "Engine Running" voltage with just the key "ON". Had replaced it because I thought that was the problem, of course it came with new pick up coil and module. Test the pickup coil resistance with a multimeter. DTC - 12 No distributor reference pulse (diagnostic test active) Nov 28, 2016 · Is it possible that i have my high/low res pulse labeling incorrect? Note that i labeled high res as the pulses that are all of the same duration. Connected battery to one side of injector, then would tap ground against other pin, injector would pulse in my hand. The service manual indicates that the distributor spark tuning reference pulses which are generated by the pick up coil are not being received by the ECM. Retrieving Computer Command Control Trouble Codes Assembly Line Diagnostic Link (ALDL)location: 1981 Model Procedure: If you have the distinct honor of having one of the first Computer Command Control (CCC) systems Aug 1, 2022 · Code 12 No distributor reference pulse (diagnostic test active) Hope this helps. Nov 6, 2009 · When the ignition is "ON" and the ECM detects no ignition reference pulses coming from the ignition module, it illuminates the Service Engine Soon lamp. rtukdtrsjhfxfzykbcj4iqlgwrkcdvvslytvrbyhk