Solid CEL+New main relay+New ECU=WTF!!!!
 

Im about to go insane, my car has been dead for three weeks now and for the first time in a long freaking time I am Fing stumped ???

The car '92 prelude....F22a1 engine

The story so far.....
Driving to work, 4 miles from my house driving about 20 mph my car just dies, no nothing just running fine one minute dies the next. CEL is on... Get it towed home and the next day start working on it. Tried to pull the code....no flashes, just a solid CEL... so I pullied the Clock Radio fuse in the engine bay (the ECU reset) and tried to reset the ECU.....nothing Still CEL.

Started to dig around in the engine bay and noticed the timing belt had slipped to one side and was rubbing itself away on the cover (it was 1/3 gone) So I was thinking....okay must have slipped off the timing, lost compression and threw a code....and the ECU is bad
I replaced the timing belt, and bought a new ECU (chipped p06 from Dustin)....---- ---- ---- it wont start.....same solid CEL !!!!

Okay so I picked up a new main relay today since I didnt hear the fuel pump prime during ignition....figured that was why the ECU was on the fritz, plugged it in and................SOLID ------- CEL!!! and still no fuel prime
Ive been over the ECU grounds (yes the thermo ground is good). I tried the Manual Diagnosis from the honda shop manual (unplug Map, EGR, & TPS one at a time unti the CEL turns off) and nothing

I really am fresh out of ideas. I'd do a proper ECU wire check, but I suck at wiring and I get a 0 voltage reading from D19 & D20 (honda manual says check these leads) Anyone willing to help????? Any ideas? Anyone willing to loan me an ECU check harness so I can do a proper diagnosis??

Cash to the person that gets my car running

Re: Solid CEL+New main relay+New ECU=WTF!!!!
 

Sounds like you got a problem.

Re: Solid CEL+New main relay+New ECU=WTF!!!!
 

So after sleeping on it....here is the plan of attack....

1. Check for 12v to the main relay....
2. Check for Voltage from ECU to main realy (should be 3 wires right?)
3. Check ground for main relay (where is this?)

I think there is power to the relay, I felt it 'click' but I dont think the ECU is sending signal to it, so after that....

1. Check Power into ECU (Which wire or wires are these....what label/pinout am I looking for in the diagram)
2. Check ground out from ECU (I know the main ground is at the thermostat, but what pinout?)

Are there any more power relays between the ECU and a power source?

Re: Solid CEL+New main relay+New ECU=WTF!!!!
 

tstat ground?

Re: Solid CEL+New main relay+New ECU=WTF!!!!
 

Thermo ground is hooked up...but havent taken a resistance reading yet

Have a list of about 5 things to check voltage for tomorrow....this is messed up :S

Re: Solid CEL+New main relay+New ECU=WTF!!!!
 

Problem solved.....

I feel like a dumbass newb ::) :1 :1Fuse #4 Back up lights.....also Main relay fuse.....replaced it and powered it up :1 :1

Didnt know that was the Main relay fuse until I followed it in the wiring diagrams