1987 BBII relay switch to fuel pump
#1
1987 BBII relay switch to fuel pump
This relay is laying on fender well, passenger side. It burned to a crisp, both parts. I am pretty sure it has to do with the fuel pump, because when I connect two of the three wires, the engine starts and runs really good and when I disconnect the wires, the engine will turn but will not start. Do not know what the third wire goes to. I do want to replace the relay, but do not know what to ask for and I do not have the old one to take with me to the parts store. Any help, please?
#3
One wire will be to going to the device, one wire will go to a ground, and the other wire will be going to an "Enable" signal line that turns the relay on or off.
As a general rule of course. The fuel pump relay is designed to be on at all times the engine is running, or while starting. It uses also a prime function via the computer to power on the fuel pump(s) for about 4 seconds when the key is just turned to 'on' but not start.
Reason I bring this up? You've got 3 leads. One will be "hot", one will be "Ground" and the other line will be for the switch 'on/off' You can use a test light, and a few turns of the ignition key to 'on' to locate the signal line. Any parts house should carry replacement relays, and from the sounds of it? You'll probably want to pick up a socket. (wiring diag. will prove helpful as to how to wire in the replacement).
S-
As a general rule of course. The fuel pump relay is designed to be on at all times the engine is running, or while starting. It uses also a prime function via the computer to power on the fuel pump(s) for about 4 seconds when the key is just turned to 'on' but not start.
Reason I bring this up? You've got 3 leads. One will be "hot", one will be "Ground" and the other line will be for the switch 'on/off' You can use a test light, and a few turns of the ignition key to 'on' to locate the signal line. Any parts house should carry replacement relays, and from the sounds of it? You'll probably want to pick up a socket. (wiring diag. will prove helpful as to how to wire in the replacement).
S-
#7
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#8
Hope this is last question about the relay. I have ordered a socket and relay thru Napa. According to them, it is a 3 prong socket and relay. (I do have 3 wires)
I do know mine was green. Do you think we are on the right road?
Thanks
#9
Heres what the factory diagrams show for the relays:
EEC relay solid yellow wire is hot key on or off
Red/light green stripe & black/light green stripe are hot with key on
Solid red is hot with key on.
Pump relay solid yellow wire is hot key on or off.
Solid red, tan/light green, orange/light blue are hot with key on.
FYI the PCM grounds the voltage on tan/light green to close the relay & turn on the fuel pumps.
EEC relay solid yellow wire is hot key on or off
Red/light green stripe & black/light green stripe are hot with key on
Solid red is hot with key on.
Pump relay solid yellow wire is hot key on or off.
Solid red, tan/light green, orange/light blue are hot with key on.
FYI the PCM grounds the voltage on tan/light green to close the relay & turn on the fuel pumps.
#10
FWIW, the fuel pump relay and the EEC relay are essentially the same relay (except maybe for case color). If your EEC relay and socket are still intact, you should be able to use those to compare.
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