QuestionQUESTION: Hello, I've been trying to figure out this problem for 3 days, its my daily driver van has been perfect for all these years and miles. The Other day I came home shut it off 1 hr later and of nowhere It wont crank at all. I tested everything that I knew about it and with the diagrams I had and it seems that the PCM is the cause of the problem, It doesn't let the starter, fuel pump, injectors, and coil pack to energize. As far as I see this, the PCM doesn't provide ground. What could be causing this? I replaced the ignition switch and even tested the wires, swapped relays. I get clicking on the ASD relay as soon as I turn on accessory or ignition on. Please help I'm currently looking for a car as I desperately need to get to work and back on my own anymore.
ANSWER: Hi Mike,
I would set aside the issue of the ASD relay. That appears to be operating normally as following the initial click when you turn the key to 'run' it will not close again until you have the engine rotating via the starter motor action.
So the issue is really the starter motor circuit. You need to see if there is a click from the starter motor relay when you try the start. If not, then either fuse 10 under the dash or the P/N switch is not closed (move the shift lever slightly off the detent position on either side, that is what should cause the PCM to ground the relay operating coil). If it clicks, but the starter motor solenoid switch is not make its loud click then either fuse 23 in the power box under the hood is blown or the brown wire from relay to the solenoid switch is 'open'. I assume you are not getting the loud click from the starter motor solenoid switch. If the fuses/wire/relay are all good then you should see 12v appear at the solenoid switch on that brown wire. If you do, and there is no loud click then the solenoid switch is bad.
So check those out and let me know.
Roland
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QUESTION: Hello Rolland
The relay for starter does click when I turn to START. There is no power to starters brown wire. but the relay and the fuse are good I have checked them multiple times with test light as well as visual.I also checked the the power distribution center for possible corrosion. ALso check the connectors on the bottom of the PDC. If I was to ground the starters connector on the bottom of PDC starter DOES turn. Other connectors grounded would allow the fuel pump to operate continuously. Starter is brand new I replaced the old one(which seems to not be the problem anyway) I Benchtested both starters and they work. I Also got a used PCM with the same exact numbers and it doesn't change a thing. I guess the PCM does not allow circuits for the starter, fuel, inj, ETC to even attempt to start. Am I looking at a possible bad wire or some module plays a role with telling the PCM to activate Start, fuel etc.? ignition switch is tested to be good, but maybe wiring towards the PCM Is bad? Also there are no check engine codes as if nothing happened.
AnswerHi Mike,
I don't understand what you mean by "If I was to ground the starters connector on to bottom of the PDC starter DOES turn".
By that do you mean you are grounding the starter relay's ground wire (dark blue/tan at pin 4 of C8 at the PDC)?
Then that is expected. But that is simply self-activating the starter relay (making it click) so if you can also make the relay click by using the key in the 'start' position then that too should cause the relay to send current on the brown wire to the starter motor solenoid switch.
So IF either way the starter relay can be made to click, then both ways should equally activate the solenoid switch of the motor. The relay can't distinguish why it is being 'grounded' but if it is, then it should operate the solenoid regardless. Possibly the "click" caused by the PDC is a "faux"/weak click because the dark blue/tan (or maybe it is tan only) wire from pin 4 is not making a good connection to pin 8 of plug 1 at the PCM.
The only other cause for that weak click would be if one or the other of the PCM ground wires is poorly connected to the - post of the battery. Those ground wires are on pin 10 of the plug 1 at the PCM and at pin 50 of plug 2 at the PCM and they both go to a splice near the battery where they get connected to the black 10 gauge wire that goes to the clamp on the- post of the battery. Those are the only explanations I can offer.
Maybe I don't understand you.
Roland
PS: Please consider doing a "rating/nomination" of me
