I just got in from work, im taking a brake form the car tonight. Will take time to rethink all. Tomorrow i will start from the beginning. Im going to receck the main wiring harness in side the car. Also the vin# matched the pcm. Im sure this will end up being something simple thats been over looked.
Help Please
- Thread starter Jim5208
- Start date
wmburns
SN Certified Technician
Was thinking about this and have some ideas. We know there's a ground on the high speed fan circuit (CCRM pin #17) that shouldn't be there. Further we know that the CCRM stopped clicking when pin #17 was de-pin'ed. What if we take an old fashion test light (something that would load the circuit) put one side on battery positive. Put the other side on the body harness side of Pin #17? As long as the pin #17 is grounded the test light should light.
This will give us a way to monitor the circuit "live" in the manner in which it's used.
The first test to do is to verify that the test light goes out when the key is turned off. IF the test light does NOT go out that proves the line is still grounded.
IF the test light does go out, that implies the ground is coming from the PCM.
The next test should be to remove the PCM and see IF the test light goes out. Then ground the signal return at the PCM to confirm that the test light does indeed light up. This will prove the signal return line can carry a signal and we have the correct terminal at the PCM.
This test set up should also offer a solid method to "wiggle" test the wiring harness looking for faults.
This will give us a way to monitor the circuit "live" in the manner in which it's used.
The first test to do is to verify that the test light goes out when the key is turned off. IF the test light does NOT go out that proves the line is still grounded.
IF the test light does go out, that implies the ground is coming from the PCM.
The next test should be to remove the PCM and see IF the test light goes out. Then ground the signal return at the PCM to confirm that the test light does indeed light up. This will prove the signal return line can carry a signal and we have the correct terminal at the PCM.
This test set up should also offer a solid method to "wiggle" test the wiring harness looking for faults.
I'm redoing this test. With lead of test light on battery positive, touching unpin 17 at ccrm, unpinned at pcm connecter, key off, no light.
With green/red pinned at pcm Key off touching unpinned 17 at ccrm, no light at test light.
With Key on touching unpinned 17 at ccrm, still have test light lead connected to positive battery unpinned at pcm, No light at test light.
With key on, green/red connected at pcm. Touch unpinned 17 at ccrm with test light, test light is flash, injectors are pulsing.
Unplug injector 5 or 6 or 8, injectors will stop pulsing, test light stays on, turn Key off test light goes out. With Key On, If I unplug injector (#7) 5,6 and 8 stop pulsing, test light goes off.
If I unplug 1-4 injectors Fan kicks on. Still have 17 unpinned from ccrm.
Unpin Green/Red at pcm, touch it to ground, light on test light is on. Green/Red is able to carry a load.
With green/red pinned at pcm Key off touching unpinned 17 at ccrm, no light at test light.
With Key on touching unpinned 17 at ccrm, still have test light lead connected to positive battery unpinned at pcm, No light at test light.
With key on, green/red connected at pcm. Touch unpinned 17 at ccrm with test light, test light is flash, injectors are pulsing.
Unplug injector 5 or 6 or 8, injectors will stop pulsing, test light stays on, turn Key off test light goes out. With Key On, If I unplug injector (#7) 5,6 and 8 stop pulsing, test light goes off.
If I unplug 1-4 injectors Fan kicks on. Still have 17 unpinned from ccrm.
Unpin Green/Red at pcm, touch it to ground, light on test light is on. Green/Red is able to carry a load.
