Help ! Arch When Removing Relay From Battery

[2500HD 8.1]

On my 2005 Yukon Denali, while I was disconnecting a headlight relay from the auxiliary battery terminal (the little red box near the alternator), I completely forgot to disconnect the battery (duh), and my ratchet arched on the alternator mount.

 

Now the car dies out immediately after starting, the headlights dont work, and the keyless entry doesnt work. I'm sure pretty much the whole electrical system, but those are the things that I have discovered so far. I'm hoping that a fuse blew, and not the PCM or something else major.

 

Any suggestions? Any specific fuses to check. I have checked some of them. How can you tell if the larger ones are blown?

 

Hopefully I dont have to tow it to the dealer.

[rjirvine]

Is there a fuseable link between the positive terminal and the red box that may have fried? You can easily check with an ohmeter.

[2500HD 8.1]

The fusable link between the red box and the alternator is OK. Im running to the parts store to test the alternator. A friend said that I may have blown a dial in the alternator? I'll check the fuseable link between the red box and the battery. Not sure what the black box/relay is attached to the positive battery cable?

[rjirvine]

If your ratchet struck the alternator housing while trying to remove a nut from the red box, the current would have come thru your ratchet to the red box to the positive battery terminal. I'd venture to say the fusible link from the red box to the pos battery terminal is toast, as tha'ts a direct short. I'd check that before going further, You may have more problems too, but that would be a prudent starting point in my opinion.

[2500HD 8.1]

I dont see a fusable link from the red box to the positive battery. It appear to be just one thick battery cable. My headlights work but the power door locks don't. I checked all the possible fuses and they are all good.

 

Still no luck!

[rjirvine]

I went and looked at my 2000 silverado, and youre right, no fusible link to red box. There is one from red box to alternator. Sounds like getting the alternator check would be the next best bet. Did you check ALL the fuses in the engine compartment and the drivers side dash (next to the door)?

[2500HD 8.1]

I did not get the alternator checked because all the crapppy parts store cant test it for various reasons. All fuses are good and I checked most of the viable relays with my 04 Avalanche.

[neonhomer]

I wonder if the PCM is okay, cause the truck will run for a sec then die. If the PCM was hosed, i don't even think it will crank.

 

You could try disconnecting the negative battery cable (from both batteries if they run the truck) for about 15-20 min to reset the PCM. While you are waiting, check in the underhood distribution center for blown fuses. IIRC, there is a fusible link between the battery and this center that provides power.

[2500HD 8.1]

Thanks guys. Battery disconnect/reboot didnt work. Its weird, I'm thinking I fried a computer or it has something to do with the security/theft deterrent system. The fuse box has power from the battery and no blown fuses or relays (that I could find).

 

The radio, power windows, and power door locks are the only things that dont work (other than the vehicle dying out). Hopefully I'll find out tomorrow from the dealer.