2009 Cadillac DTS

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Oct 17, 2009
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#1
Make
Cadillac
Model
DTS
Year
2009
Miles
101000
Engine
4.6L
Today my 2009 Cadillac DTS would not start, after driving it today 400+ Miles. I suspected fuel pump issue since it cranked but just not start. I did find the fuel pump relay with burn marks on its exterior sides. I replaced it and now it is running fine. My question is, why would the relay burn up like this. Since I am currently traveling I am now very concerned braking down on the highway. What are your thoughts????
 

billr

wrench
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#2
Carry a spare relay. Pry the cover off the old relay and post some pictures of what got toasted in there, as well as pictures of the spade terminals that plug into its socket in the relay/fuse panel.
 
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#3
I think you will be fine. They do go bad and the newer the vehicle the worse the problem may be due to poorer quality metals being used in many electrical components. Enjoy your trip and do not worry too much about it.
 
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#4
Thanks guys for the feedback. The relay is burnt at pin labeled 30. I have installed a new relay and it cooked that one also. I checked the current draw on the circuit and it is only 8 .5 amps. I did have it checked with thermal image camera and it showed heat being generated at the base of the fuel pump relay. So today I bypassed the fuse panel completely, and installed an external relay. So far doing good as far as the fuel pump circuit. But now my rear door power lack and unlock no longer work. I assume the G301 wire that I removed from the fuse panel and connected directly to the new external relay must be needed for other circuits besides the fuel pump. I looked on line for a schematic of the rear fuse panel but I was not able to fine it. If that is something you could pass on to me that would be great!!!!! THANKS!
 
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#5
Make a pin that is slightly fatter than the leg of the fuel pump relay and jam it into the appropriate hole (pin 30?) on the fuse panel, and you will likely have power to the door locks again. (yes, of course you will have to connect a powered wire to your fatter pin) I am just trying to offer a shortcut to getting the door locks working again (probably).
 

grcauto

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#6
Today my 2009 Cadillac DTS would not start, after driving it today 400+ Miles. I suspected fuel pump issue since it cranked but just not start. I did find the fuel pump relay with burn marks on its exterior sides. I replaced it and now it is running fine. My question is, why would the relay burn up like this. Since I am currently traveling I am now very concerned braking down on the highway. What are your thoughts????
You should be fine. If you have a spare that's good if not you can swap out another relay long enough to get you to a parts place.