Battery draining out overnight

[berg07]

My car is a 1991 Camry GLI 2.0. I'm not particulary good with electronics so I'll need some help to fix a battery drain.

Questions:

• What is a normal drain in a 1991 Camry?
• How much drain are the different electrical components supposed to cause?
• How do I continue troubleshooting after knowing behind which fuses the problem is located?
• Where do I find the headlight relay?
• How do I control the function of a relay with a multimeter?
• In what way can the fact that I recently hade my starter checked and fixed relate to my newfound battery drain?

Problem:

My battery is draining out overnight. Without anything left on.

Background/info:

I have just had my starter fixed by a local dealer. Now I've encountered the problem of my battery draining out too fast, just over one night. The battery is brand new, about a month old. The temperature here is about 0 degrees Celsius at night. I have not left the the lights or radio on. The problem started just after I had my started checked and fixed. As long as my battery is loaded the car starts every time at the first attempt.

The alternator is working fine - giving about 14.4 V with the engine running.
I don't think there's anything wrong with the battery either. I've loaded it full with a charger so it's able to recieve energy.

My conclusion was that I have a battery drain. So I did a test with a multimeter in the same way as described here: http://free-auto-repair-advice.blogs...attery%20drain

I first made sure that no light is litten in the glove box or the trunk.
With my multimeter in 10A-mode I got a 0,19A reading with no lighs on or doors open and the key in off-position. With the door open the value rises to 0,46A.

I started troubleshooting to find the source of the drain.
I disconnected my non-original cd-changer. No change in value on the multimeter.
I pulled out every fuse in the fusebox in the left kick panel (driver's side) one by one. No change.

I pulled every fuse in the fusebox located in the engine compartment. The only change I found was that the reading dropped 0,06A when I pulled out the 20A-fuse named "DOME".

I also pulled out the fuses in the fusible link box near the battery. Removal of the 40A-fuse named FL MAIN caused the meter to drop 0,07A.

In this wiring diagramme http://www.camrymanuals.com/manuals/90/90_EWD.pdf I found out that the 40A-fuse is connected to the headlight relay. And that the "DOME" fuse is connected to lots of things. (See pages 40-41 in the manual linked above)

I pulled the cables from the alternator as well - no change.

Summary:

With everything shut off, doors closed and the key not even in the keyhole, I have a constant 0,19A drain.

By pulling out fuses I've been able to make the drain smaller:
Constant drain 0,19A
dome-fuse -0,06A
Fl main fuse -0,07A
= 0,06A ----> 60mA = drain with both fuses removed.

So back to the questions again:

• What is a normal drain in a 1991 Camry?
• How much drain are the different electrical components supposed to cause?
• How do I continue troubleshooting after knowing behind which fuses the problem is located?
• Where do I find the headlight relay?
• How do I control the function of a relay with a multimeter?
• In what way can the fact that I recently hade my starter checked and fixed relate to my newfound battery drain?

[Doctor J]

Wow, your post sounds like engineering report !
If the car is sedan, pull the light bulb out of the trunk light .If battery is not discharges after that , the switch in the latch for the trunk lid needs adjustment.

[berg07]

Originally Posted by Doctor J

Wow, your post sounds like engineering report !
If the car is sedan, pull the light bulb out of the trunk light . If battery is not discharges after that , the switch in the latch for the trunk lid needs adjustment.

Yes the car is a sedan. Forgot to write that.

With the trunk lid closed the trunk light is not on. With the trunk open the light consumes 0,3A (plus the constant drain of 0,19A, making the total drain 0,49A). I could try to remove the light bulb, but I don't understand how the circuit can drain any current since the light doesn't shine?

If the problem is in the switch in the latch for the trunk lid, how do I fix it?
What does the switch look like and where's it located?

And what about the drain related to the headlight relay? The headlights are working properly by the way.

[Doctor J]

If the light in the trunk is OFF when the trunk lid is closed, the problem is not there.With constant drain of .19 amps times the 10 hours period, the battery looses only 1.9 AmperXhours, which is less then 5 percent of the battery capacity. Thus the battery still must be able to crank the starter.
how many volts is on the battery
- before the start
- with key in the start position?
Measure voltage at the battery posts,not on the cable terminals.

[berg07]

Originally Posted by Doctor J

If the light in the trunk is OFF when the trunk lid is closed, the problem is not there. With constant drain of .19 amps times the 10 hours period, the battery looses only 1.9 AmperXhours, which is less then 5 percent of the battery capacity. Thus the battery still must be able to crank the starter.
how many volts is on the battery
- before the start
- with key in the start position?
Measure voltage at the battery posts, not on the cable terminals.

Thanks for answering!

The voltage has roughly been somewhere below 12V the times it hasn't started (see text below). I can't give you any more exact figures right now as I have charged the battery.
How low can the voltage go before the battery can't crank the starter?

Ok. My car is constantly draining 0,19A and the capacity of the battery is about 60Ah so it shouldn't be able to loose too much current over one night.
10 hours x 0,19A makes 1,9Ah which is 1,9Ah/60Ah = about 3 % of the capacity of the battery fully loaded.

Why should I measure the voltage with the key in the start position? (I will do it...just wondering why...)

My battery was probably not fully loaded when I parked for the night last time. But after two nights I could not get any lights on at all. The battery was completely empty, showing 0,01V with the minus terminal removed. The drain was 0,08A at this point. So I jump-started the car, drove about 20 km, shut off the engine. The voltage was then about 12,4V with the terminals attached to the battery. After about five hours of charging with a 8A-charger the voltage was 12,2V with the minus cable deattached.

Another time when I wasn't able to start the car the voltage was about 11,8V after one night, measured at the battery posts with the cable terminals attached.

What is exactly the difference between measuring voltage with the cable terminals attached or not?

Measure voltage at the battery posts, not on the cable terminals.

The way I usually have measured the voltage of the battery is with both cable terminals attached to the battery posts.

What is a normal drain in a 1991 Camry?
I checked the drain in my father's ´89 Camry. It was 0,01A. So my drain is 19 times bigger.

[Doctor J]

Measuring voltage under the starter load will show the battery's cranking ability, it must be around 9 volts.
if the battery terninals are corroded the voltage on tne cable terminals will be lower then on the battery posts.
In the shop here we are using 12 v 3.4 Watts light bulb with probes attached (or commercially available test light with the same bulb) which is connected to the terminals of pulled out fuse. If the light is off ,then the drain is acceptable, as the clock, the fade out relay on some models and the engine control unit memory are always connectd to the battery power.
I would like to suggest to take look on the starter battery terminal, make sure the cable is correctly attached.
Why the starter was rebuild at the first place?
Are the interior lights dim when you put the key to start and engine is not starting?
Is there any noise from the starter solenoid at that time( loud single click or rapid clicking)?

[berg07]

Fast answer again, thanks.

The battery terminals are clean, the battery is new (about one month old).
The voltage is the same when I measure with the multimeter sticks at the posts and at the cable terminals.

I checked the cable terminal at the starter and it looked all right. I also unhooked the smaller cable above to see if it would affect the drain. It didn't.

I haven't got the kind of testlight you have but my constant drain is 0,19A. This is as far as I know too much.

The starter was fixed because the car wouldn't start even though the battery was fully loaded. All that happened when I turned the key was a click. It wouldn't even crank. After the starter was checked out the car has started at the first attempt as long as I have had enough power in the battery.

This morning the car had been parked for two nights. When I tried to start it absolutely nothing happened. The battery was completely dead. I couldn't even get the instrument panel lights lit. No clicks, no nothing.

[Doctor J]

I re-read all your post again what is really strange that even the bad batteries still have 6 volts on them without load.0 Volts on the battery is possible only if the post is broken inside(the conductor shunt inside is corroded).
If I would be local to you I will definetely take a look on the car.
For now I will suggest
-to charge and check the battery
to pull the dome fuse out to see if the battery will stay charged.

[Mike Gerber]

Doctor J seems much more knowledgeable about electrical problems than I am. I would continue to follow his advice. However, I thought I would mention one thing that I have seen cause a severe dark current draw like this. That is a malfuctioing aftermarket alarm system. By any chance do you have an aftermarket alarm system on this vehicle? If not, ignore my post and good luck finding the dark current draw.

Mike

[berg07]

Originally Posted by Mike Gerber

Doctor J seems much more knowledgeable about electrical problems than I am. I would continue to follow his advice. However, I thought I would mention one thing that I have seen cause a severe dark current draw like this. That is a malfuctioing aftermarket alarm system. By any chance do you have an aftermarket alarm system on this vehicle? If not, ignore my post and good luck finding the dark current draw.

Mike

Thanks for your concern.

Actually Mike,
I do have some kind of fake alarm system. I don't know who's installed it neither did the previous owner.

As far as I know the only thing this fake alarm system does is to keep a very small light blinking in the rear window. The light is a small bulb built into the rear window breaklight. While I was checking the amount of drain I unmounted the bulb. The drain was still 0,19A with the bulb gone. So I don't think if it's the fake alarm system.

How can I troubleshoot the fake alarm system further?

There's only one un-original cable attached to the minus post on the battery. I don't know to what it's connected, but the drain is the same with and without it connected.

[berg07]

Originally Posted by Doctor J

I re-read all your post again what is really strange that even the bad batteries still have 6 volts on them without load.0 Volts on the battery is possible only if the post is broken inside(the conductor shunt inside is corroded).
If I would be local to you I will definetely take a look on the car.
For now I will suggest
-to charge and check the battery
to pull the dome fuse out to see if the battery will stay charged.

I agree that the 0 V situation is very strange. But I charged the battery for about five hours today and it gave me 12,3 V. As mentioned earlier the battery is very new. The car started directly with 12,3 V.

I've left it with the minus cable off for the night.
I know that with the dome fuse gone the drain decreases with 0,06A making the total constant drain 0,13A. So that's still too much?

[berg07]

Immediately after I parked my car today the voltage in the battery was 12,5 V, measured with a multimeter.
Six hours later I checked the voltage again: 12,01 V. The temperature outside was about -2 Celsius.

According to the diagramme showed here (chapter 6.): http://www.batterystuff.com/tutorial_battery.html
this means that the capacity of my battery dropped from about 75% down to 25% in six hours.

If this is correct it seems like very fast drop in capacity?
How can a 0,19 A drain reduce the capacity in my battery that fast?

[Doctor J]

If the battery discharged while being disconnected fom the car, the problem is the battery itself.
The separator in one cell may crack, allowing the plates of opposite polarity to touch.
the battery must be exchanged for the new one, if it is under warranty.

[berg07]

Originally Posted by Doctor J

If the battery discharged while being disconnected fom the car, the problem is the battery itself.
The separator in one cell may crack, allowing the plates of opposite polarity to touch.
the battery must be exchanged for the new one, if it is under warranty.

Sorry, I wasn't speaking straight enough. The battery was connected to the car when it went from 12,5 V to 12,01 V in six hours.

Today I'll be checking how much it loses while being disconnected from the car.

[TBayToyotaBoy]

That fake alarm system you have seems suspicious. Are you certain it is only a little light, and not an actual alarm? Are there any spliced-in wiring harnesses under your dash, or around your fuse panel? Any small brain boxes under there?

A friend of mine had an old aftermarket alarm in his Jeep plow-truck and it completely ruined the truck (wouldn't start). He ended-up scrapping it because removing the alarm was so complicated without manufacturer wiring diagrams.