Radio causing parasitic battery drain

[davetib]

Hello everyone,
Here's the backstory. 2003 8 cyl 4x4 Explorer. Had a parasitic drain on the battery and found the culprit was Fuse #28 - Radio (Start) / DVD (Start). Pulling 500mA with fuse in and 20mA with fuse out.

So I pull the wiring harness off DVD. Nope, not the problem
Did the same with the amp and the radio. Pulled all plugs from the radio and still pulling 500mA.

So I thought maybe it was the thingy that tells the radio to turn off after 10 minutes. So plugged everything back in and tested. Radio turned off in 10 minutes just like it's supposed to. Now I'm perplexed.

Everything else in the vehicle is working perfectly. If I pull fuse 28, all is right with the world, but no radio.

Anyone have a clue what might be the issue here?

Thanks,
Dave

 

[4D X]

Is that the stock stereo?

 

[davetib]

yes...should have mentioned that off the bat. This is the stock radio/cd changer that came with the vehicle.

 

[davetib]

It just sounds like there's something else hanging on that circuit that's not in the fuse description.

 

[lincolnshibuya]

doesn't make sense, that fuse is only active when car is running (IGN ON), there's no connection when it's off. how did you do the parasitic tests?

the GEM module sleeps after several minutes (forgot how long) to prevent drain, might be something on the door, alarm system that keeps it awake most of the time.

 

[davetib]

Hey lincolnshibuya...

Here's how I did the parasitic test:
1. Disconnected negative terminal on battery
2. Set Multimeter to 10A setting
3. Connected positive lead on meter to negative battery cable
4. Connected negative lead on meter to negative battery post.

As soon as the connection is made, you can hear relays and stuff kick in. So I let the meter hang for 15 or 20 minutes.

With Fuse 28 in - Radio Start / DVD start - I hang right at 465mA. When I remove that fuse I drop to 20mA. I tested every single fuse in the box near the battery, and random (about 10) fuses from under the steering wheel. Nothing except the Radio Start fuse made any difference.

And yes... I totally agree. There's no way that fuse should be an issue, but there it is. I was shocked when I unplugged the harness on the DVD player, AMP and radio and STILL had the problem.

--
Dave

 

[davetib]

I should also mention... With Fuse 28 removed, the radio does not work.

 

[lincolnshibuya]

the only way you could have connection there is via the ignition switch, is there a voltage in that fuse even when the truck is off?

might be a faulty ignition switch or some short on that area.

 

[davetib]

I'll check the voltage across the fuse with the truck off. That's a good idea.

 

[JoeMcc]

How old is your battery and has it been tested. Had this same problem with my Escalade. Spent two months trying to find a problem. Had battery tested by advanced three times and checked out good. Replaced alternator and still would be dead the next day. Left battery unhooked for three days and started fine. Finely bought a new battery and now sits for weeks at a time with no problems.

 

[davetib]

JoeMcc - The battery is brand new. This is number 3. The first had a bad cell. Ok..sounds good. Then a month later battery won't hold a charge. Ok..they replace. A couple days after that, battery is dead.
Humm...No way this is a battery problem. That's when I pulled out the multimeter and started checking for a battery drain.

 

[Ramboscie]

Check this fuse under the steering wheel, it's further uplne, when I put pull it my 400mA drain disappears and the total drain drops to 200mA then 60mA after 20mins as it should. My radio is my 400mA drain issue, even with the ignition off. The battery saving circuit/system won't activate while this 400mA drain is present, so my total drain is always 800mA while that fuse is in, thus my battery goes flat after 4days.

 

[Kellyr1]

Hello everyone,
Here's the backstory. 2003 8 cyl 4x4 Explorer. Had a parasitic drain on the battery and found the culprit was Fuse #28 - Radio (Start) / DVD (Start). Pulling 500mA with fuse in and 20mA with fuse out.

So I pull the wiring harness off DVD. Nope, not the problem
Did the same with the amp and the radio. Pulled all plugs from the radio and still pulling 500mA.

So I thought maybe it was the thingy that tells the radio to turn off after 10 minutes. So plugged everything back in and tested. Radio turned off in 10 minutes just like it's supposed to. Now I'm perplexed.

Everything else in the vehicle is working perfectly. If I pull fuse 28, all is right with the world, but no radio.

Anyone have a clue what might be the issue here?

Thanks,
Dave

I have 2003 Ford Expedition Eddie Bauer, and it has similar battery drain condition. It appears to be tied to the bass amplifier above the bass speaker in the interior rear panel. The bass speaker intermittently makes a deep popping sound when I start the car and when I shut it off, with a delay of about 5 seconds in each position. With the radio on of off. I noticed I had battery failures coincident with when I hear the bass popping. When there is no popping noise, I do not get any more battery drains. But then the popping noise resumes a few days later, the battery is drained if the car is not used for a few days.

I traced the problem by disconnecting the cable harness to the amplifier. Access to the amplifier is by lifting up the storage tray and immediately below is the amplifier and wiring. It was hot to the touch when the key was not in the ignition and the battery was drained. I disconnected it and let it cool. I charged the battery and stated the ignition and the radio an hour later and then re-connected the amplifier and heard the popping sound and the music played as normal. I cycled the connector a few times and the bass came on and off as expected. Since I found that symptom and reconnected the harness, the popping sound has not returned. But I keep the storage tray loose so the next time I hear the popping sound I will disconnect the amplifier and verify that the battery is not dead in the morning.

I don’t have a cause of the amplifier intermittently draining amps while the ignition is off. But I would like some opinions of the forum.