Yesterday I turned left and my car killed. Sitting there on the side of the road...again....I notice the radio's not working as nor are any dash warning lights. headlights and wipers are, but the motor is not. When I turn the key to try to start the car nothing happens. No starter, no dash lights, nothing. So I check the battery terminals and still nothing. Then I check the underhood fusebox and find that the "ignition sw" fuse is burnt. I robbed the "power windows" fuse to replace it as the amps are the same.(30 amps) When I try to start the car the fuse blows again. Now understand, I don't have to switch to start. When I turn the key to the run position the ignition sw fuse blows. So I took all the fuses and relays out of the box..( yeah I made a cheat sheet to put them back properly), put a fresh fuse in the ignition sw slot and began replacing each one by one waiting for the fuse to blow. It was when I put the 60 amp " fusible link" fuse back in that the damn ignition fuse blows. I am aware that it is most likely a short somewhere, I was just wondering if anyone can narrow down my search. I'm not too quick to condemn the ignition switch as the short because in the run position a lot of other things are on at the same time. I appreciate your time and response.

 

Okay, today I traced the wiring. The positive battery cable to the starter looks okay. The negative cable..ditto. The four smaller white wires from the positive terminal feed the fusebox under the hood and they checked out. Visually anyhow. Wiring under the fusebox looks good. The wire that comes off the fuse that keeps blowing is a white wire that goes ...yes...to the ignition switch. Removing the steering colunm cowl nothing looks burnt there. Options...pull all the interior fuses and replug them one at a time until the ignition fuse blows....actually unplug everything (distributor, PCM, sensors, etc.) and replug....jump the fuse that blows and see what burns....nah, I don't like that idea. Is there a device to hook up to the system and detect a short in a certain item?

On a related note, the parts house here have no more 30 amp fusibles...for now.

 

Get an ohmeter and check the white ones for continuity as these are fusible links

 

BV, continuity? Wouldn't that suggest an open in the wire? With the fuse blowing like it is I would think it would be a short. I picked up a tester today but I am not to familiar with the operation. Sooo, I unpluged every fuse, relay, dist., and PCM and repluged them starting with relays, then fuses, dist., and finally PCM. The fuse didn't blow. I started the car and was able to get about a mile down the road before the fuse blew again. Got to be a short huh? You know, I had the problem of the battery terminal hitting the hood. Think the PCM, interior dist. wiring, or ignition switch could have an internal short?

 

i've had one car that the white fusible link was too resistive (should be under 1 ohm) this one was several 1000 ohms and was pulling excesive current intermittantly...
It seemed more likely to act up in wet weather I found the end closer to the battery terminal had corrosion that had leached down into the wire under the insulation

 

Okay, tracing wires sucks! I traced the wire to the ignition switch and disconnected the connection and found the black/white wire to be the culprit. Eventually I got my hands on a schematic for my car and found that the wire in question supplies 5 different items. These being fuel pump relay, the evaporative emission ventilation solenoid, PCM, electrical EGR transducer solenoid, and the EATX-ECM. So I disconnected all of these items, replaced the fusible link that keeps blowing and replugged each item one at a time. Go figure, after weeks of the fusible link blowing, it dosen't blow. I had previously disconnected all of the items with no luck. The EATX-ECM is the only item I had never messed with. Is it possible that it reset itself when I unplugged it?

 

doubtful ... I'm betting you had a resistive connection going to one of the other items and unplugging them might have cleared up the corrosion