: 2008 DTS fuel pump relay keeps burning up

08-21-13, 11:58 PM
I Got the Caddy back in feb of 2013 with only 66k miles. Now the fuel pump relay keeps burning up its the same prong that keeps burning. The dealership wants 160 just to check it which is bs. I wrote one expert online he was saying that it was the female connector where the relay goes which was loose, so i bent the the connectors foward which gave it a better contact but its still getting hot as hell n at idle feels like its about to give. I already been through like 4 relays in a month. I need one of my Cadillac Forum bros to help me out with this one.:thepan:

08-22-13, 12:24 AM
bad connection will do that every time try squeezing the connection thats burnt alot tighter together so that it is very tight to the relay when you put a new one in if it doesnt work replace the problem connection with one that does or replace the fuse box if you have a junk yard close buy get one from another from a caddy btw sweet ride

08-22-13, 01:27 AM
Read this thread


You can add a Bosch relay without replacing the fuse box

08-22-13, 09:38 AM
Big caddy I'm gonna try that out bro


Danog I wanna rewire it but it seems there's only one wire going into the fuse box for the fuel pump relay. I'm guessing the rest is wired inside the box some where.

08-22-13, 07:33 PM
Even if you went to a dealer and paid the diagnosis money, you might have problems convincing them to do repairs - they'll stop as soon as they see the jury-rigged wires jammed into the 30A and the 5A fuse sockets. Someone has grossly messed up the fuse box - that may be most of your problem right there.

If someone tried to insert another wire in the hot side of the pump relay sockets and jam in a relay, that has bent the socket clamp fingers open and you have a high resistance connection = fire or burnt relay(s).

The crude mess of wire ends sticking out of the fuse box positive (red) feed isn't helping, either.

These cars are insanely demanding of perfect wiring practices - until all that's corrected you're grasping at straws.

EDIT: Zooming in on those pictures, several of the sockets in that fuse/relay box are damaged beyond repair. Time to head for the junkyard - same car/year/model - and replace the box and make proper connections. That fuel pump sucks up a ton of electrical current (It's pushing gas at 47 psi) and it runs the entire time the engine is running - so every connection in that circuit has to be perfect. There are several LARGE electrical connectors behind that fuse/relay box.


You'll spend a lot of time and money correcting someone's electrical mistakes. Spend some of the money on a subscription to www.alldatadiy.com so you can access the wiring diagrams in order to get the proper ignition and hot wires you need to run all the aftermarket installs - What's the oval black box under the fuse/relay box ?? If it's an aftermarket alarm or remote start, that can be the cause of a LOT of weird electrical problems, too - like horns honking, lights flashing, trunks opening, and dead batteries.

08-23-13, 12:30 AM
Thanks for the reply man. The two wires u seen are turn on wires for my audio system they are connected to that oval shaped box you were asking about. I unplugged them for now. So when you say rewire my aftermarket stuff are you refereeing to taping into them before they touch the wafer side of the fuse box? Or what do you prefer?