Hey so I just opened up the ecu and found out that in my 91 Civic Si is a PS9, from what I have found from two different sources it is supposed to be a PM6. If you have been keeping up with my electrical nightmare! I am wondering one, would this be the cause of the door latches and brakes and horn shorting out and draining the battery the way they have been all of a sudden after running fine?

And second, does this ecu even work to keep in the car? Obviously I would rather grab the original and put that in instead, but I can't afford much more into this car.

It is about to be scrapped after two weeks of digging through wires.

Thanks I can really use some good advice for this little guy right about now.

 

PM6 is correct, PS9 I believe is the automatic EX ecu. I couldn't tell you if that thing is the cause of your problems. You mention "keeping up" with your nightmare, can you link the thread(s) you have posted?

 

ps9 = automatic obd0 ecu for the a6. i have two of them... yes it will run your car, but you will throw codes and a cel for the auto shift solenoids

 

https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/terrible-electrical-problem-seatbelts-2724215/

Here is the original post for a lot of the wiring questions I had come up with. If you know this stuff at al I am having a really hard time pin pointing the culprit right now. Thanks!

 

pgmfi.org has info on how to change the ecu to a manual i do obd1 ecus all the time no biggie