|Quote, originally posted by Dubluva »|
|I'm using this post to put an ABA in my pickup. I'm having a problem with the following and hope you can help me. I'm still improving my "electrical skills " I'm using an aftermarket relay for power and have the following connected:|
Red/Blue 12 ECM Power Supply Relay(87)
Black/Brown 20 ECM T68/9 - ECM " "(85 as marked on relay)
Terminal 30 - 12v power
Terminal 86 - controller (switched power)
My question is about the brown/white engine block ground. It is grounded through the harness to the front of the block, but what has to be done to ground the ECU? As it is, the relay has no ground to close the circuit, and I'm not sure what is the best way to ground it. I hope this makes sense. Any help is appreciated. Also..after its all said and done, how can I know the ECU is powering up before I turn the key?
Brown/White at the panel end, should just be connected to any suitable ground. I'm not sure if this goes directly to the ECU or not, but the wires that I listed gives it everything that it needs.
If you're installing your own relay to provide the power (I used existing wires from the factory relay panel), you'll just need to give it suitable power and ground too. You should not ground the relay using the ground wire from the engine harness - they both need to be grounded to the -ve of the battery, via the body of the car usually. I'm not sure if that's what you meant, but i think it might be.
I do not know of a way to test for the ECU being on without cranking the car, sorry. As long as it's getting power and a ground, it should be one, but won't actually output much until it sees spark (from my understanding). Maybe the bentley provides some pinout tests for the ECU? Just be careful with your wiring and you should be A-OK.
On a related note, i just installed my ODB2 ABA into my rabbit truck - if anyone has a spare ODB1 harness, i'd love to switch mine over