2000 S80 battery drain

hu5ker555 · Post by **hu5ker555** » 30 Jun 2013, 20:01

I have a 5 amp battery draw, measured between the neg battery post and neg battery cable. This is with everything off (except the lights in the trunk because I the trunk is open during the test).

I've pulled fuses and relays one at a time. The 5 amp draw drops to about a 3 amp draw when I pull fuse 32 (central electronic module, interior lights, power steering). My interior lights are not on. So it seems something on fuse 32 is pulling about 2 amps. Don't have any idea where the other 3 amps are coming from.

Please help!!!

Post by **JDS60R** » 30 Jun 2013, 23:28

5 amps is such a huge draw with the car off I have to ask how you are measuring it?
Most meters will go to 10 amps. Are you seeing 5.0 or .50 amps?

If you are actually looking for that large a draw while off, you may want to disconnect the main lead to the alternator to see if a diode has failed.

Otherwise a standard parasitic draw test will locate the issue for you.

hu5ker555 · Post by **hu5ker555** » 01 Jul 2013, 06:50

Thanks for the quick response. My multimeter runs up to 10amps, so I'm pretty sure it's pulling 5 amps.
I tried pulling the wires off the alternator (there is a large wire bolted to the center and a much smaller connection on the front). Took them off and did not see any change. Still pulling 5 amps.

Post by **jimmy57** » 01 Jul 2013, 09:01

close the latch on trunk lid with a screwdriver. The power down phases go faster that way.
Open all doors and hood and then close all door latches the same way and then just the left side hood latch. That way you have all access but don't have the confusion of CEM waking and restarting the power down every time you open/close doors.

CCM, PDM, DDM, and DIM fuses are good places to start once alternator has been eliminated as source of power consumption.

hu5ker555 · Post by **hu5ker555** » 01 Jul 2013, 09:23

I'll give this a try with the latches.

I pulled the main wire to the alternator previously and that did not change anything.

hu5ker555 · Post by **hu5ker555** » 01 Jul 2013, 12:52

Thanks for the responses. I did check the alternator and there was still 5 amp draw.
I'll try closing the latches and looking into these other fuses.
Starting to wonder if it might be the alarm system. I've read that a bad alarm battery/module could be drawing current. I didn't see a fuse in slot 38 for the alarm, and not sure how to test this.

hu5ker555 · Post by **hu5ker555** » 02 Jul 2013, 07:03

I have pulled each and every fuse and relay one-by-one. Disconnected the alternator. Still getting 4 or 5 amps of current draw.

Only thing left I can think of would be the alarm system. Is there some way of disconnecting it to isolate this? Other ideas?

hu5ker555 · Post by **hu5ker555** » 02 Jul 2013, 18:25

UPDATE

Still have 5 amps draw. Everything on the car works, except for the alarm siren. When trying to activate the alarm, the lights on the passenger side of the car flash on/off, but not the drivers side. I tried to trip the alarm by having my son (19) in the car, turning on the alarm, then crawling into the trunk and pulling the battery cable. No siren.

Thinking that the siren is the problem, I then accessed the siren through the wheel well. Disconnected the wire to the siren. Still 5 amp draw!!!

Could the siren still be the problem? Please help!

hu5ker555 · Post by **hu5ker555** » 06 Jul 2013, 07:52

Looks like I'm headed to the dealer.

Aaaaaaaargh.

hu5ker555 · Post by **hu5ker555** » 09 Jul 2013, 10:56

OK. So I took the S80 to the dealer. They tell me that my battery is failing. Just need to replace battery. Also noted that the siren is not working quite right, and may be failing soon but that the siren is not causing the battery drain.

I had previously taken it to Autozone, where I actually bought a new battery. Once they put the new battery in and tested it, the battery was being drained. Autozone told me that it was not a battery issue, but a significant power drain. They gave me back my old battery.

So, I'm having the Volvo dealer replace the battery today and then run it through whatever testing they can to make sure it's not draining.