Battery draining constantly; Flux capacitor problem?

[hall.nathan89]

So I'm having a problem with my battery dying and I can't figure it out. As far as I can tell, nothing is on when the car is off (I've gone around listening/looking in a quiet place at night) but the battery is still draining and after 8-10hrs, the car won't start anymore. I had the battery and the alternator tested, and both tested good. I charged the battery all the way and it lasted 4 days.

I know the real answer to this is a date with a multimeter, some long test leads, and an extra-large helping of patience. But is there a faster way to troubleshoot this? It wouldn't be a problem except that it's my daily driver and I think my coworkers are tired of letting me jump my car from theirs.

[SteveJ]

More data is needed here. What modifications have been made to the electrical system? Alarm? Stereo? Amplifier?

When you go at it with the multimeter, measure the current through the battery, disconnect the alternator, and measure again. If the reading drops with the alternator unplugged, that is likely your problem.

[Carl Beck]

Just some thoughts...

The most common cause I've seen of the sympthoms you describe - other than a bad battery - is loose or corroaded battery terminals. The first thing I'd do is pull the terminals off, clean them down to bare metal - both on the battery and on the wires. Then reconnect them making sure they are tight. Second most common is alternator belt tension too loose.

Lots of people look at the terminal connections - they "look" OK and they don't go any farther. Take them off and clean them the make sure they are TIGHT.

Then Sit in the car after the battery is fully charged - and the car has been stopped/not running for a few hours - then put a finger on each individual fuse - see if any of them feel warmer than the others. That might give you a clue as to which circuit to check.

I know you had the battery "tested" - but did they perform a proper "Load Test" on the battery? Many auto parts stores fail to perform this test, or don't have the test equipment to do it in the first place. Batteries can hold a surface charge until they are put under a higher load - such as in starting - then they short out and go dead under a higher load.

With a good battery - fully charged - you should be able to leave the parking lights on for several hours, without a problem restarting the car.

Good luck

Carl B.

[Zed Head]

One cheap way to see if you have a draw on the battery would be to make up or get a test light and connect it between the negative terminal and the battery post. A pseudo ampmeter. If there is current flowing you should get a glow. Then start pulling fuses or fusible links or disconnecting possible loads until it goes out.

If the light doesn't glow at all then the battery load test would be the way to go.

Also, if the top of the battery is dirty and moist current can flow between the positive and negative terminals.

[hall.nathan89]

Thanks for the input! There is a new stereo in the car (previous owner installed), there's no alarm and really no other electronic devices that aren't original. I think they did a load test, but I'm not positive, so I'll ask.

I'll admit that I'm guilty of the "They look clean" mentality; I'll clean them and check my cables tomorrow and see how it goes from there.

SteveJ: What are your thoughts given the things I've just stated?

[SteveJ]

A question to me usually gets a few more directed back at you.

1. How long have you owned the car?

2. How long have you had the problem with the battery draining? Was it like that when you bought the car?

3. Do you have a power antenna?

4. Are you charging the battery every day?

5. How old is the battery?

With a battery constantly dying, it's usually one of two problems. There is a load that is not being switched off, or the battery is not charging properly.

An alternator that is dying can be a load on the battery. An improperly installed alarm can be a load. (Usually this is a case where something was supposed to be installed on a switched circuit, but it was installed on a constant on circuit.) If the ignition switch does not properly go from Accessory to OFF, relays will be energized that would normally be off. A malfunctioning power antenna can be a load.

Of course, an old battery can have trouble maintaining a charge. Internal resistance can cause it to die. For example if you charge the battery, disconnect it from the car, and it still runs down, then the battery has issues.

After cleaning connectors as Carl suggested, also go through the FSM section on the charging system. If the S130 FSMs are set up like the S30 FSMs, you'll find it in the Engine Electrical section. Ensure that the alternator is charging the battery properly.

[Wade Nelson]

Did you get this problem solve? How about an update on what you found.

If not I can probably lead you to a successful diagnosis,