ok so i did an extensive search and came up with a few possible causes but none to explain this: my ecu fuse keeps blowing whenever i turn the key to the on position.
let me tell you guys what happened first. my car got stolen and as a result when i got it back there was a bunch of blown fuses. the ignition switch was broken and they had all the wires cut and bunched togethor(i guess to hot wire it). but anyways i replaced all the fuses that were blown and the ignition switch. but whenever i replace the ecu fuse and try to start it, it blows. so i checked to see if there was a blinking light at the ecu and there was none also my CEL light does not come on. i also noticed a burnt wire at the under hood fuse box, its a small yellow wire that im guessing pluged in at the slot next to the ecu fuse. now does any one know where this wire comes from and if its the reason for my ecu fuse blowing. i checked my mfr and it is good. i also checked fuse #24 and its fine. so any other help would be greatly appreciated.
You’re not going to get a CEL or blinking codes on the ECU with the fuse blowing.
You definately have a short somewhere, are you sure you fixed the harnesses properly?
yes i repaired the wires good. it was only the ignition wires that were cut, so thats what i replaced, but as i mentioned before there is one wire under the hood that got charred. so my question then would be where does this wire go to and what does it do? its the little wire that comes out at the fuse box under the hood. its yellow with green i believe. its like an 18 gauge wire so its one of the thin ones. it looks to me theat it should plug into the empty slot next to the ecu fuse. also i did a lil more research and came up with nothing. if any one has the wiring schematic that can help me out with this. all i need to know is where this little wire goes to. thanks
any one please help me!! i need to get my car running so i cav smog it and tag it since when they stole it they took my plates and they were up for renewal anyways. but yeah it sucks that i havt to drive my beother s-10 blazer that gets 15 mpg while my teg just sits there. can any one point me in the right direction here. please 80 something views and no one replies. thanx for any help in advance!
sounds like your going to have fun. What when your starting the car how long does it tke for the fuse to blow and what happens
I don’t know if I can help you but I will try, first I need more info, I need to know when the fuse blows, as soon as you install it or when the ign. is turned to acc., [position 1] or when the ign. is turned to run, [position 2] or when you crank the engine to start, [position 3]?
I do not have wiring diagrams for g2s, but looking at g3s the only yellow/green wire from engine bay fuse box I can find is the power for the fuel pump relay, and that is on a 98 teg, it is black/yellow on 94-98 tegs and they have power on them when ign. is in the run, [2] and start, [3] positions.
Also going to the relay and the ECU is a blue/white on 94-98 tegs it only has power when cranking to start.
There is also a white/blue on 94-98 tegs that go to the ECU power all the time, and a yellow/white that goes to the relay also hot all the time.
The black/yellow, [94-97] and the yellow/green. [98] hot when ign. is in the run or start position are the power for the fuel pump, [once fuel pump relay is triggered] and the “trigger” for one of the relays inside the fuel pump relay box that connects the yellow/white, [94-98] hot all the time, to the ECU.
As you can see the “wiring” is complicated so to find out what is causing the fuse to blow I need to know when, exactly, the fuse blows.
The problem may be in the ECU itself, you can check that, but not eliminate it by disconnecting it, if the fuse still blows, it may just be a short in the wiring, [around that burnt yellow/green wire, you may have to cut the harness open to fallow the wire to see if it is burnt farther along and shorting out other wires.
The other thing you can do is, [if you can borrow one] just plug in an ECU that you know works, if the fuse does not blow and the car works you know where the problem is, however if there is a problem with a short in the wiring for the ECU, you take the chance of damaging the working ECU :uhoh: 94
I’m in Bakersfield as well. I have a '92 RS but I do have the haynes manual on your year as I am using the loom from a G2 for my B18 powered mini swap.
I’ll email you my cell #. should be available this weekend.
hey i double checked the wire and it looks like its a yellow with white one. the yellow with green is fine. also i peeled back some of the wire loom and it looks like no other wires were harmed. so my question remains: Where does this yellow/white wire go to and what does it control. also i got no sound from the fuel pump, and no spark, and the injectors are not firing. another thing is it blows the fuse when i turn the switch to the ON position. so either this little wire is causing all my troubles or i have a bad ecu. but i want to get this wire fixed before i go ahead and buy another ecu.
Yellow/white goes to the ICU, ECU, TCM (if automatic), and the seat belt control unit.
Have you repaired the wire where it’s melted, or at least kept it from touching the metal on the car? Have you repaired/replaced the ignition switch harness properly? Did they muck with any underhood wiring or underdash wiring besides the harness going to the switch?
Try disconnecting the ECU from the harness and see if the fuse still blows.
Also, the fuel pump, injectors, CEL, etc won’t work - your ECU isn’t getting power.
i havent repaired it because i dont know where it plugs in to. but heres other things i noticed dont work: headlights, emergency flashers, wipers, fogs, and seat belts. but yet all the fuses are good axcept the ecu fuse and that little wire is not hooked up… so i think it plugs into the slot next to the ecu fuse in the fuse box. but not sure, any other things i should check for?
If I’m reading the diagram right (which I’m probably not), the white/yellow also powers your seat belt control module - so your seat belts won’t work until it’s repaired. Try at least insulating the wire and seeing if the fuse stops blowing then. And yes, it plugs into that box - I snapped a pic of how mine looks to help.
Outside of that, it sounds like your column wiring is FUBAR - probably be a good idea to rape the column wiring out of a junkyard teg at this point. Your fog light switch is powered by the headlight switch, so that won’t work until you’ve got power going to the headlights again.
I highly suggest investing in a Helmes manual at this point, along with a good multimeter and a case of beer. At the very least, swap out your harnesses in the steering column and fix that melted wire, and see if any other under dash wiring got butchered.
thanx for the pic. i replaced the switch and the wiring, but other than the wires for the ig swicth there doesn’t seem to be any other wires under the dash that got trashed. so i’ll fix the wire and plug it into the slot and then go from there. where can i get a helms? i know autozone, pep boys, and kragen dont carry them.
They’re probably pretty hard to find by now - I think they’re out of print.
Send me an IM or an email and I’ll see if I can help you out.
ok so i cut the loom as much as i could and found that the wire did not melt into any other wire but it is stuck to one of the ignition wires. the white w red. so what ima do is run a separate wire to the ecu pin out where this wire once went to and just leave the burnt one there. any who i took my ecu out and it smells burt. like you know when something electrical starts smoking? but yeah thats what it smells like!!! im about to take it apart to see what happened.
opened it up and found it has a capacitor like thing burnt. everything else looks good but i dont think its fixable. so im prolly just gonna practice desoldering chips and soldering back in so that when i get the next one i can chip it myself
thanx
wilcax: you really need to check your email. I emailed you a link on like Tuesday you will probably find interesting.