My PM7 ecu on my 88 CRX appears to have a grounding issue. I have lost tach, fuel level, temperature, directional signals, and AC compressor function (fans come on but compressor never engages) - pretty much everything that depends on the ecu for their grounds. The engine actually runs very well. I don't know if the IAC valve is even working.
I'm hoping first of all that someone can give me a pinout on the ecu (OBD0/PM7). Also if anyone with any info on this issue could respond it would be greatly appreciated. I have also tried three different ecu's with same results.

 

PM7 pinout is the same as the PM6
Are your ground wires at the thermostat housing connected, clean and secure?

 

I know that now. I just discovered three fuses that blew around the same time. That led me to believe it was something in common so the ecu came to mind. I have just resolved the issues. Thanks for responding.