PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

PCM seems powerless

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Old Dec 15, 2008 | 07:33 PM
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Default PCM seems powerless

Ive just put the motor back in and im trying to fire the new motor. The motor will turn at the request of the key but it doesnt prime the fuel pump, try to run, and the SES light doesnt seem to come on at all. It makes me thing the PCM isnt getting power/signal.

The 2 PCM related fuses underhood are good and supplied with power.

Ive tried 2 different PCM's.

Everything else about the car seems to function.

The car has no transmission in it. I have 2 wires shorted to fake out the neutral switch. (Does the trans have to be in the car??)

I was wondering what part of the harness might I not have hooked up that would cause this. I have 2 pigtails under the dash hooked up coming from the engine harness, was there another??

Thanks for the help.
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Old Dec 15, 2008 | 08:48 PM
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Pinks and oranges are the power wires
Pink for ignition power and orange for battery power.
Pull your blue PCM plug and make sure they have power
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Old Dec 23, 2008 | 10:07 PM
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Im getting power to those 2.

I want to trace grounds now. Are there any others than the 3 small ones that go on the back of the head?

The battery has one small cable going to the shock tower and a large one going to the frame rail. Its fastened with a bolt holding the strap going to the motor. The 3 small grounds check to be grounded to the battery.
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