This is probably an easy one for some of you out there.

I went to start the '87 Vette in early March, and it was completely dead after sitting for a few weeks. New Optima in early January. Other one lasted ~7 years. It just started getting weak, so I replaced it.

I put the trickle charger on it and after ~ 4hrs charging it started fine. I noticed after I was done driving that when I went to re-start (you must turn the key on and let it go through a complete fuel pump energize cycle, then start on 2nd energize, as it pulls a lot of fuel and f.p. will drop to ~15 psi when cranking), there was a strange "hum" after the fuel pump circuit shut down without car running. It sounds like it might be coming from the R rear area, and almost sounds like the hum from the radio speakers. I made sure the radio was off. Put the car away amd turned off the battery disconnect.

I pushed the car out in mid/late March and then switched the battery cutoff to the "ON" position. The key was not in the ignition, but that same "hum" was present. The car started no issue.

I think the "hum" is what drained the battery. Any thoughts on what the "hum" may be in the R rear or rear area of the car? Thoughts on how to pimpoint the issue?

Thanks in advance,
Aaron

 

a buddah meditating? look for a big fat guy.

 

Got Bose? If so, I'd check the Relay.

 

Fuel pump.

 

only a few things that can hum back there. the fuel pump, bose amps/relay, antenna motor on left side, and my high school sweetheart .....I'd start pulling fuses and you'll at least find which circuit. -Harry

 

Thanks for the reply guys:

Well the fuel pump is not the answer, as there is no mistaking the sound of the Weldon. The radio was off, so the power antenae was also down, so I think that is out. Not the HS sweatheart, as I would definitely know that sensation.

Where is the Bose relay located?

Thanks again for the replies.
Aaron

 

don't assume your antenna is not the culprit.

pull the radio fuse and see if it goes away. I don't have the FSM in front of me, but someone w/ radio knowledge hopefully chimes in on your other relay question.

 

The antenna still works up and down so I assumed that it was not the power antenna relay. You know what they say about assumptions...

 

well alright, I'd assume that your antenna is working OK too. plus the noise you say is on your right side (pass).