Calling subaru people... Fuel Pump voltage troubleshooting help.

[KrazyKid]

@Boxersix

If your car is AWD, you have a factory fuel temp sensor as well hence the weird readings and extra wires.

Those older cars used to run the fuel pump off terminals 1 and 4… black wire, and black wire with red stripe. B-R being the 12V signal.

Test/replace the relay first. They do go bad. Basic quad pole relay.

Note…You need to test for voltage at the pump clip at immediate key-on. The PCM primes the pump for ~3 seconds, then kills voltage until the motor starts. Turning the key on, then going in back to test it will typically yield no voltage signal as the prime sequence completed.

Man I didnt want to get under the dash and hunt for that relay. But its a normal 4 pole relay, like I could use a regular old square back 30a automotive relay?

I know about the priming, I had my brother turn the key while I had the volt meter on the terminals. Pin one is dead as a door nail.

Now I read a thread about a guy with the same problem, he replaced the relay and still didnt show pin 1 voltage, he then replaced the pump and it worked, even without the voltage? Who knows about that though.

So Pin one is powers the pump for a few secs to prime then pin 2 runs it constant? and pin 3 is the fuel temp sensor?

Thanks for the info so far.

240- yeah its right under the rear hatch carpet, doent even have to take a seat out or anything.