Fuel Pump Relay

So my car died on the interstate today, noticed that my fuel pump fuse was blown, I stole the headlight fuse (same rating of 7.5amps) and put it in. The fuse popped right away, didn't even start the car. Took off the fuel pump relay and noticed that the prongs were all black and discolored. Prob bad and want to replace to narrow my search. My question is, how many prongs should the relay have, the one I took out but my research has shown that it should have 5? What's the part number of the replacement? I found 61-36-8-373-700 which is the 5 prong. Thanks a lot.

Originally Posted by Bimmerkid325i

So my car died on the interstate today, noticed that my fuel pump fuse was blown, I stole the headlight fuse (same rating of 7.5amps) and put it in. The fuse popped right away, didn't even start the car. Took off the fuel pump relay and noticed that the prongs were all black and discolored. Prob bad and want to replace to narrow my search. My question is, how many prongs should the relay have, the one I took out but my research has shown that it should have 5? What's the part number of the replacement? I found 61-36-8-373-700 which is the 5 prong. Thanks a lot.

The five pin relay is effectively the same as the four prong relay....it just has two of pin number 87....connected together inside the relay. So you could make a four pin relay work by joining together the wires that go to the two 87 pins.

You can diagnose the blowing fuse problem by leaving the relay out and jumpering pins 87 and 30 together and try use an Ohm meter to measure the resistance of the pump circuitry so that you can try locate any short without have to use up a pile of fuses.

I jumped the 87 and 30 pins on the relay and got .4 ohms resistance. Where do I go from here?

I also installed a new relay, still blew a fuse.

usually fuel pump has a 20 amp rating fuses. look for the correct amp rating fuse that will be a good stary

Sent from my Nexus 7 using Bimmer App

The owners manual said it should take a 7.5 amp fuse? Am I correct?

Originally Posted by Bimmerkid325i

I jumped the 87 and 30 pins on the relay and got .4 ohms resistance. Where do I go from here?

Disconnect the fuel pump and see if you still get that .4 Ohms reading....you obviously would expect an open circuit with the pump disconnected, if not then you have the wires shorting somewhere.

Try running a pair of wires direct to the fuel pump from the battery....with a fuse inline.
If it blows then the fuel pump is shorted out.

So I found out tonight that the fuse still blows with a different fuel pump put in the car. I decided to disconnect the plug that connects to the fuel level sensor in the tank and what do you know the fuse didn't blow and the car kept running. Of course I don't have the gauge to work anymore but now I know the system to look into more. Any ideas on where a potential problem might be? Im going to look at the back of the cluster I think but otherwise don't really have any idea :/ thanks for the help!

You'll have to examine the harness for the fuel circuit, by tracing it rearwards and looking for damage/scorching, abrasion where it is clamped or passing through grommets.


m

Thanks and that's going to be exciting haha. I'll try this weekend. Thanks