ECU not getting power

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Lockleaf

New Member
1989 CRX HF. Just swapped in a D16Z6. Running OBD0 PR3 ecu. Using CRX original wiring harness. Removed Injector resistor box, using D16 injectors. Using CRX original distributor and oxygen sensor.

My computer is not powering up. I don't even get the one single blink from the LED as I turn on the key. Because of the ECU I am not getting the fuel pump to run or prime. Injectors are not spraying either. ECU is not grounding them out. Main relay is not the problem. It has been inspected, and then replaced with new anyway. The fuses under the hood are all good. The "solenoid" fuse under the dash is also good. Thermostat ground has been cleaned with a dremmel and bolted tightly. I also added two or three additional grounds between the engine and chassis just for good measure. I have not run the vtec wiring yet, but that should not matter for just powering up the ecu.

I have probed A13 at the ecu and it has power. I have continuity between a16 and the chassis, which I am pretty sure means that my ground is good. I have double checked every fuse and they are good. My main relay (which is two relays in one box) kicks over to send power to the injectors but does not power up the fuel pump. i can jumper power from injector yel/blk wires over to the fuel pump wire on the back of the relay and the fuel pump will kick on but otherwise it is dead. Injectors will not pulse even when the fuel pump is engaged.
 
Power at the ECU but ECU not powering on?


Sounds like a bad ECU to me...
 
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just a heads-up - when using the PR3 ECU in the CRX HF, you need to cut the green with black stripe wire at ECU pin B9 - otherwise, you will get a check engine light when you shift into reverse
 
so we have discovered that if we disconnect connector C from the ECU, the ECU turns on, fuel pump primes and injectors will pulse. obviously the car will not start because that disconnects the TPS and a bunch of other sensors, but the moment we connect that connector back up the ECU shuts back off. we are depinning the connector to remove wires one by one until the ECU turns on but any thoughts?
 
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