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I'm sorry, but I'm a little confused on what specifically you need my help with. Can you clarify whether you're just seeking a professional opinion (basically an educated guess) on what could be wrong, or are you looking for technical guidance on how to diagnose and repair the issue yourself - might need access to tools such as bi-directional scanner, scope, fuel pressure tester, etc.
OK WE ARE A SHOP WE DO HAVE FUEL PRESSURE WE REPLACED ECM MODULE AS WE WAS TOLD THIS WAS PROBLEM BUT WAS NOT WE STILL HAVE A NO START CONDITION TESTED ASD RELAY ITS GOOD TO
I understand. Do you know if there any current or pending codes? Will the engine start with starting fluid?
Need to step out. Be back tonight to check on your progress.
NO START WITH FLUID ALSO P1389 IS THE CODE
ALSO REPLACED CAM SENSOR
Thanks for that information.
Code P1389 sets when there is no ASD relay output voltage at the PCM, which can very well be the reason there is no spark or injector pulse.
Check fuses 6 and 26 in the PDC (see attached graphic) and make sure there is voltage going in and out of them. If OK, then go to the Gray connector plugged to the PCM and check there is voltage at the Dk Green/Lt Green wire going to pin 12 (see other attached graphic).
Please let me know what you find.
OK GREAT HELP NOW WHERE DOES THIS WIRE FROM THE PCM FEED FROM TO GET ITS POWER TO IT THE ASD RELAY ?????AND THANKS GREAT HELP
OK MY PIN #12 IS GREEN WITH A WHITE TRACER AND NO POWER TO IT AT ALL EVEN CRANKING THIS FUSE DIA ISNT LIKE OURS AT ALL I WILL CK AGAIN FUSE #6 AND #26 OK IF THIS IS THE PROBLEM WHAT FEEDS THIS WIRE ????
Power comes from the battery + to the fuse box under the hood (PDC) where it goes through fuse F6 to terminal 30 of the ASD relay. Once the ASD is energized, power comes out of terminal 87 on a Dk Green/Orange wire to splice S128 (on the harness near breakout for PCM) where it branches to feed the injectors and coils and goes back into the PDC where it feeds fuse F26. Then goes through F26 on a Dk Green/White wire to PCM pin 12.
OK SO THEN THE GREEN WITH WHITE TRACER SHOULD BE HOT WHEN CRANKING CORRECT JAUN YOU HAVE BE A GREAT HELP
JAUN WHERE CAN WE FIND DIA ON THIS WIRING ROUTING SYSTEM TO SEE WHERE IT BAD AT SIR ????
OK. Take the ASD relay out and turn the ignition switch on, then take a voltmeter and check voltage and grounds at the empty socket (see previously attached graphic); there should be voltage at terminals 30 and 86; then, have a helper turn the key to START while you check for ground at terminal 85.
Please let me know the results of those checks so I can have a better idea of which diagram can best help you.
OK ON #30 GOOD VOLTAGE ON #86 GOOD VOLTAGE NOW ON THE GROUND TERMINAL #85 IT WAS 11.86 OK AT THE BATTERY IT WAS 12.11 SO THERE WAS A 0.26 DROP OK
OK. That actually sounds like the power circuit is OK up to the ASD, but it (the ASD) is not being energized (when you wrote "TESTED ASD RELAY ITS GOOD TO" I assumed you had tested its circuits as well)
The PCM is supposed to apply ground to ASD terminal 85 as soon as the ignition is turned on (if engine is not started within the next 2 seconds, PCM will stop applying ground to 85) and then, as soon as it sees the ASD output voltage at pin 12 and a crank signal, it keeps it grounded as the engine starts and runs.
Check continuity on the Dk Blue/Yellow wire running from terminal 85 to PCM connector C3 pin 3. If wire is good and there is continuity, then whoever told you to replace the PCM was right - as a retired Chrysler Master Tech, I always recommend using factory parts that include the latest software upgrades and carry the best warranties.
OK WE WILL TEST THIS BUT JUAN THIS IS A BRAND NEW PCM
OK ON THAT CIRCUIT ITS ONLY AT 0.3 OHMS AINT THAT LOW ????
Low Ohms means low resistance which means good continuity.
Regarding the PCM, remember we tested the ASD circuits assuming the PCM was getting ignition voltage and the grounds were good. So, before replacing the PCM, make sure the following is happening:
OK ALL CKS OUT NOW QUICK QUESTION ON THE INJECTORS WHY WONT IT SHOW A SIGNAL WITH NOID LIGHTS BUT IT WILL WITH THE 12 VOLT TEST LIGHT GROUND ISSUE???JUAN
OK JAUN WE WAS DOUBLE CKING ALL FUSES FUSE 18 IGNITION KEEPS BLOWING 15 AMP KEY COMES OUT OF THE SWITCH ALL THE TIME CAN THIS BE THE ISSUE ALL THE TIME ITS ONLY HOT WHEN THE SWITCH IS TURNED TO THE START POSTION SIR
ALSO TECH TRACED WIRE TO ENGINE BLOCK BP PLUGS AND REGROUNDED IT TO BE SURE
Sorry for the delay; I usually don't work on weekends.
If all checks out as you say, then the PCM should fire the injectors and light-up the Noid light.
Fuse 18 protetcs the horn circuit and should have nothing to do by itself with the no start condition.
I just noticed you had two questions open on the same topic; one with me, one with expert Daryl. You need to close one of those questions for us to be effective.
OK SORRY JAUN GET AHOLD OF ME ON MONDAY THEN OK THANKS
I see you still have the other question open. I'll opt out until the issue is resolved.
I CLOSED THE OTHER TECH OUT WE NEED YOU JAUN ON THAT FUSE THAT BLOWS ALL THE TIME ITS SHOWS FROM ALLDATA ITS A IGNITION OUTPUT START IT ONLY BLOWS WHEN YOU TRY TO START IT