I need someone to look at the wiring of my relays and tell me why they are set up this way. Every year, about this time, I need to replace a relay because my fuel pump doesn't engage. It's obvious that the fuel pump relay is the culprit, but when I get it, it looks more like the relay on the far right ( oval shaped) than the middle relay.

Also, the Chevy dealer that fixed my car in the past told me that my car was incorrectly wired. They never fixed it. I see that the tan/white wire with the orange wire setup (5 wire connector) is connected to the MAF burnoff relay and the other connector is going to the fuel pump relay. That relay has a light orange, dark orange, black and blue wire. I believe these 2 relays are interchangeable, but I want to make sure. I'm almost positive that the tan/white wire should be going to the middle relay. Can someone point me in the right direction? Will it hurt to just swap these harnesses to the opposite relays? TIA.

 

I just dealt with my relays for my car, so ill try to help from what i remember.

The Tan wire with the white stripe is used for more than just the fuel pump relay. it also runs the fan relay.

the oval shaped relay (far right) is the fan relay. it has a 12Vin(black big wire), 12Vout(black with purple stripe, big wire), and then a 12V trigger (tan/white wire) and an ECM ground (should be green/white stripe).

note the tan/white wire? yes thats the same one that runs the fuel pump. RUNS the fuel pump, not triggers the relay. the fuel pump relay is triggered by the ECM, i beleive green with a yellow stripe maybe? the ECM on switches GROUNDS, never 12V, so you can safelly assume that anything being switched on and off by the ECM is definetelly a switched ground.

when the key is turned, this tan/white wire gets 12V. this powers the fan relay, and turns on the fuel pump. then the ECM removes the ground from the fuel pump relay after about 3 seconds. this turns off the fuel pump. notice its still getting 12V from the tan/white wire.

Oh yeah, and to confuse you MORE, the actual fuel PUMP is always grounded. it turns on using ANOTHER Tan/White stripped wire. this one ALSO runs to the fuel pump relay. you can tell it apart from the other tan/white wires because it is noticably larger in diameter. this is the actual fuel pump wire. if you wanted to activate your fuel pump, you just hit this wire with 12V and the pump turns on. try it.. if the fuel pump doesnt turn on then you have hit the wrong tan/white wire with 12v... the only other ones are for the relay powers, so no big deal.

This is from memory, sorry if anything is wrong, i dont see anyone trying to help so i took a stab. i could be wrong about 1 or two things, even a color or 2, so go into this with an open mind.

if your fuel pump relay is dying about once a year then there is somthing WRONG. im going to take another stab and say there may be a short, or a bad connection somwhere causing a lot of resistance to the relay, which would burn it up i think. if there is a small wire (say, freyed) thats carrying some decent amps, it can heat up the relay and pop it. I think. just a thought.

 

compliments of vader..

 

that is not the same relay setup he has, notice the fan relay is missing in that pic.

 

Best help I had...

 

Looks like a difference in years; too. GM used the oval-top'd relays in years after '86 or '88, I believe...