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View Full Version : car died! no power to ECU!


drifter808
08-08-2007, 02:21 PM
I searched but couldn't find anyone with similar problems, or maybe i just suck at searching.
so heres what happened, i was driving to go meet my girlfriend, and out of no where my car just dies completely. try starting it and nothing. no noise from fuel pump or anything. the car is cranking over just fine but doesn't want to fire up. So i had to get it towed home(what a rip off). Now today that i have time to tear it apart i was first checking the fuses and all of them looked ok and weren't blown. Then i check to see if the ECU is throwing any codes. Theres no lights or anything coming from the ECU. I've checked for codes before so i know how to do it. But nothing was coming on. I've had the same problems with an older ECu where everything looked fine inside and out but it was fried. Im gonna go test the ECU with a friends today, but im mainly wondering if anyone else has experienced this same thing and knew what the problem was. Or anything else i can test?

Thanks,Derek

nlzmo400r
08-08-2007, 02:47 PM
sounds like your ECU crapped out. I would begin searching for a short in the system if this is your 2nd ecu

steve shadows
08-08-2007, 02:56 PM
sounds like your ECU crapped out. I would begin searching for a short in the system if this is your 2nd ecu

yeah ecus just dont crap out.

Your stock wiring harness although maybe re-wrapped by the swapee upon install to look pretty is probably looking like britany spears c-section scar on the inside.

replace your wiring harness and get a new ecu.

make sure all the ground connections from the engine harness to the battery area harness are correct.

BTW you might also just had a disconnection of one of the connectons in your battery area wiring for the EGI or ECU relay, look for a black with red stripe and red with black stripe

drifter808
08-08-2007, 08:08 PM
so i checked for power at the ECU plug and its getting none. I checked the Black w/ white striped ones by the grounds. Pins 38 & 47 are getting no power. theres power going thru the harness cause other pins are getting power. I checked up at the front plugs by the battery tray and there is power coming from the car into the harness but it seems to get broken up inside the harness. Any ideas aside from tearing the whole harness apart. this is my only car and i drive it 100 miles a day to work.

makulit054
08-08-2007, 09:20 PM
Mine did the same thing. I opened the ECU to discover the solder run on the ignition(pin #36) was toast. My car started up fine. Check for any visible damage to ECU. check your harness before you get another ECU or get a new harness.

Unholy S14
08-08-2007, 09:36 PM
had a similar problem

fuel pump wasnt kicking over, turned out I had a bad ecu.

Sileighty_85
08-08-2007, 10:20 PM
i had a similar prob my harness rubbed through on the fuel injector rail and blew a fuse shutting off My PFC I freaked out everything cool now check the harnnes and wiggle the harness while a buddy tries to chrank it to see if its just shorting out some where

drifter808
08-08-2007, 10:43 PM
well i found another car to drive so i got the harness out of the car now and im tearing the harness apart. so far there are no visible defects. while its out im also gonna clean it up some and get rid of some stuff i dont need. I'll post my progress later on tonight. thanks for all the help.

also forgot to mention, the Back up power wire(red) is getting power. its just the two Black with White main ECCS power wires

makulit054
08-08-2007, 11:15 PM
check the ECU for visible damages also. shorted wires can draw large amounts of current and cause failures on the ECU.

drifter808
08-09-2007, 12:42 AM
after tearing apart the whole harness and tracing those power wires back and all over they seem to be perfectly fine. I even ran another wire through the harness just incase i decide to run a seperate power source. Any other ideas on what it could be? Or what wires to check?

Unholy S14
08-09-2007, 06:41 AM
have you tried borrowing a different ecu ?

EnthusiastMan
08-09-2007, 07:50 AM
Check your ECCS relay and fuse. You can swap your fuel pump and ECCS relay's and see if you're getting power to the ECU.

drifter808
08-09-2007, 11:45 AM
Unholys14: i haven't yet, not many on my island but i do have access to another one just have to drive there. 1 hour each way.

enthusiastman: Where is the ECCS relay?

drifter808
09-23-2007, 11:41 PM
So i thought the problem was all fixed but something else is going on now. I changed out the relay and it fixed the problem but what is happening now is the relay wont turn off. The EGI relay at the main fuse block, it will stay on and drain the battery. I wired in a toggle switch for a quick fix but want to figure out why its doing that. Any ideas???