no power to ignition

[mccomas]

I was installing a rebuilt alternator and failed to unhook my battery – ya i know... when installing the battery terminal wire to the back of the alternator, I arc’ed it and saw a puff of smoke from the driver’s side on my engine bay – looked like front area. The back of my alternator has three wires. a number 1 and 2 terminal set and the BAT terminal that attaches to a post. It was the single positive wire (BAT terminal) that I arc’ed. I am not reading 12 volts at the BAT terminal on the back of the alternator. I have no power to my ignition switch – truck will not start. I do have good battery power. I also have no voltage at my ignition fuse when measuring against ground. Other fuses location such as horn have power. I obviously smoked something. Need help.

 

[cegusman]

Sounds like you smoke the fuseable link. To bad I don't know where it is, or what it looks like.

 

[dyeager535]

My fusible links are right at the starter. Follow the orange wires off the starter and you'll find mine. You should be able to test them without getting too dirty by looking at the terminal on the firewall just to the passenger side of the brake booster. Check for voltage on those orange wires coming from the engine. If you don't have power up there, you've more than likely smoked a fusible link.

Still haven't examined my truck wiring manual about this, but typically (cars) GM wired the ignition side and the "accessory" side seperately...if you blow one of the two links, you'll either have headlights, horn, etc., or you will have ignition, one or the other, but not both.

 

[diesel4me]

there is at least 3 fusible links!~

On most GM trucks there is 2 fusible links at the starter solenoid in the thick red wires that bolt behind the positive battey cable,also another one is located at the firewall right beside the brake booster in the thick red wire that bolts to the plastic junction block thing....some trucks have one in that thick red wire from the altenator too,hidden inside the black plastic crinkle wrap that runs along the valve cover....Most likely the ones at the starter are fried--seems like the most dificult ones to get at to fix always blow most often,thanks to murphy's law...

 

[mccomas]

i found what looked like a fusible link. Two red wires feeding into the bottom of a black plastic cylinder with a 16 stamped on the black plastic (I assume 16 amps). Exiting the fusible link was another red wire that went to the plastic distro block on the firewall (passenger side of the brake booster). I had voltage at the feed wire on top but no voltage at the bottom two. With a bit of elimination and some continuity checks, it looked like one of the bottom red wires came from the BAT terminal on the alternator and the other went to the ignition. I cut out the fusible link and tied the wires together and everything is good to go. I have power to the ignition. I did not want to crank because I just had everything jumped together with no fuse protection, but I am sure that I found the problem. Going to motor over to pep boys in the wife’s Honda and see if I can find a 16 amp fusible link to tie it all back together. Thanks for the help and quick answers…