This wasn't doing this before I disconnected the battery. Long story (there's another thread about it). I disconnected the battery because it was dead. I was going to charge it outside the car. Yesterday, I had the battery hooked up and everything seemed normal except that the battery was run down. There has never been any noise since I have owned the car for a month. Took battery out. Put it back. when I tightened up the negative cable, there's a noise that sounds like an antenna that wants to go down even after it is down. An electric motor noise in other words. I thought it was the antenna on. I pulled the radio fuse but still the noise. Went to the back, opened the trunk and it is coming from where the fuel pump is. I didn't want to run what's left of the battery down so disconnected the negative.

Any idea why the fuel pump would sound off so loudly when the battery is reconnected when it didn't do it before? I have modified nothing.

 

are you absolutely sure it is the fuel pump?

or is it the antenna motor? Both are very near each other.

If it is the antenna motor running, then it must be the green Antenna Relay shorted. it is mounted next to the antenna motor.

you need to remove the floor panel, and then the short panel over the pump and antenna motors to touch them and confirm which one is running.

since you have been working with the radio, you may have connected the antenna wire to a constant 12v power wire.

 

Thanks Jose. I will look into my wiring. Actually. I couldn't have connected the antenna to the 12V constant because I connected the Jag Antenna wire to the radio antenna wire. Blue to white. I remember it well. I'll do the check you suggest in any case.

 

Well the pump shouldn't be powered, but there are relatively noisy little things. I'd guess you just never looked for/noticed the sound before.

Verify power at the pump. If it does constantly have power, disconnect the AFM and see if it still has power. Possibly check the relay to see if its permanently closed or if something is straight wired.

 

The fuel pump relay fused together on my ‘92 XJ40 so not unheard of. Same problem, FP running after the car was shut down.