doghead starter relay modifcation

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Disconnect both batteries before attempting this procedure

Credit goes to doghead for his instructions in thread "underdash starter relay" and the wiring picture as well.

This modification replaces the standard GM underdash starter relay, GM Part# 15591718 (which is prone to sticking), with a higher rated 200amp relay from Napa.

1. Buy Napa part# 7-01860-1 (SME line) (you may need to delete the dashes to find the part) or part number
7018601 (remove the dashes). The same relay can also be bought at other parts houses. (Oreilly's, CarQuest, etc)
2. Disconnect your batteres
3. Remove diagnostic port under the dash and a couple screws which will release the mounting plate for which the relay is mounted to
4. Pull the mounting plate with relay down out of the dash so you can get to it, and remove the relay from the mount plate (IMG00541)
5. Mount the new Napa relay to the mounting plate. You can use one of the existing holes and then drill the other (IMG00542)
6. Cut off the old relay from the wiring as close as you can (IMG00543)
7. Put ring terminals on, and wire to the new relay according to doghead's picture (starterrelaywiring)
8. Tape everything up well with electrical tape so you don't have bare metal sticking out anywhere
9. Replace the mounting plate up into the dash, replace diagnostic port, and re-connect your batteries
10. Start truck with confidence

Edited to add: I'm no expert btw, I just did this off of doghead's instructions and he said he had started his about 100 times with no problems. I did it, started mine, and it works.

Proceed at your own risk. :)

***Added Napa info***

***And another thread with more pictures***


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