Car died, no power to ecu (ms3), radio, inside light, license plate light, INJ FUSE
Thread Starter
Elite Member
iTrader: (1)
Joined: Mar 2014
Posts: 1,557
Total Cats: 197
From: Jacksonville, FL
Went for a tuning run, car suddenly died at WOT 2nd gear pull.
Fuel INJ fuse under hood was blown (30A), put in the headlight fuse in its place, and it instantly blew, put fan motor fuse and again instantly blew.
Towed the car home.
Only fuse that is blown is fuel INJ under the hood. and it keeps blowing as soon as it put a new fuse in it.
Checked every single fuse under drivers side dash, all are good. BUT the following parts in the car are not working:
* ECU (MS3 basic) seems to not be getting power. cant connect to it. and blue lights on the bluetooth adapter are not coming on. so i suspect no power to ecu.
* Radio will not turn on
* Inside cabin light is off
* license plate lights are off
but all fuses are good?? im stumped.
where do i even start?
Fuel INJ fuse under hood was blown (30A), put in the headlight fuse in its place, and it instantly blew, put fan motor fuse and again instantly blew.
Towed the car home.
Only fuse that is blown is fuel INJ under the hood. and it keeps blowing as soon as it put a new fuse in it.
Checked every single fuse under drivers side dash, all are good. BUT the following parts in the car are not working:
* ECU (MS3 basic) seems to not be getting power. cant connect to it. and blue lights on the bluetooth adapter are not coming on. so i suspect no power to ecu.
* Radio will not turn on
* Inside cabin light is off
* license plate lights are off
but all fuses are good?? im stumped.
where do i even start?
Well, a ton of stuff is powered from the INJ fuse. The radio/lights are not. Did you install an aftermarket radio?
I would start by removing the main relay and measuring resistance from WHT/RED to ground. If it is short, or nearly short, start disconnecting stuff that is powered from WHT/RED or WHT/BLU in turn. Measure each time you disconnect something.
I would start by removing the main relay and measuring resistance from WHT/RED to ground. If it is short, or nearly short, start disconnecting stuff that is powered from WHT/RED or WHT/BLU in turn. Measure each time you disconnect something.
Thread Starter
Elite Member
iTrader: (1)
Joined: Mar 2014
Posts: 1,557
Total Cats: 197
From: Jacksonville, FL
Thank guys for the suggestions.
i just discovered the main relay is pretty hot to the touch, even with the car off for a few hours.
bad relay or a short overloading the relay making it hot?
main relay can cause no power to radio and interior lights, and ecu?
i just discovered the main relay is pretty hot to the touch, even with the car off for a few hours.
bad relay or a short overloading the relay making it hot?
main relay can cause no power to radio and interior lights, and ecu?
Thread Starter
Elite Member
iTrader: (1)
Joined: Mar 2014
Posts: 1,557
Total Cats: 197
From: Jacksonville, FL
swapped out main relay and fuse labeled engine in drivers dash (fuse was fine, but i did anyway), disconnected injectors, coils, radio, options plug on ms3.
turned on ignition, and ms3 fired up. thank god. was worried it burned out.
connected all the accessories one by one, and all was good. car fired up fine.
also popped in the old main relay, and everything still works.
no idea whats up or what caused all this. so weird....
joining AAA today. lol.
turned on ignition, and ms3 fired up. thank god. was worried it burned out.
connected all the accessories one by one, and all was good. car fired up fine.
also popped in the old main relay, and everything still works.
no idea whats up or what caused all this. so weird....
joining AAA today. lol.
Last edited by borka; Jun 20, 2018 at 12:57 AM.
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