Annoying Battery Drain In A '82

[toobroketoretire]

The battery in my '82 will go so dead in a week the clock won't even work. I have my 6 amp trickle charger on it (with the ground cable disconnected) and I noticed it's only charging a low 2-1/4 amps when dead batteries normally charge a full 6 amps. The battery is only 1-1/2 years old but it could be defective. I was having a problem with my courtesy light timer as it wasn't turning the lights off; only dimming them. So I replaced the delay module but that didn't help the situation at all so the problem is elsewhere. As long as it's started every few days it starts okay but after one week it'll be down to 3 volts; indicating a drain somewhere.

Can any of you think of a common source of a battery drain in the later C3's?

 

[Antz81]

Did you get around to pulling fuses to find it? If you and but nothing came up it only leaves the lights or the alternator as the cause. But if that battery is charging properly it may be a good idea to get it tested.

 

[toobroketoretire]

Did you get around to pulling fuses to find it? If you and but nothing came up it only leaves the lights or the alternator as the cause. But if that battery is charging properly it may be a good idea to get it tested.

I have a gut feeling it's the battery that is at fault because my 6 amp trickle charger is only charging 1-1/2 amps when it should be charging 4-5 amps. I'm going to take the battery to the auto parts store and let them charge and test it.

 

[toobroketoretire]

Getting Closer To Finding The Problem

Okay, so I finally got around to pulling the fuses AFTER I took a close-up picture of the fuse block so I could easily put the fuses back in without mixing them up. The moment I pulled my radio fuse out the drain stopped but when I put the fuse back in the drain wasn't there any more (???). Right now my battery is reconnected and fully charged and I'm checking it's voltage every morning. So far it's holding it's own so maybe the drain has quit. Perhaps the radio or power antenna has a tiny short that was causing the drain. Just glad it's a spare car and not my daily driver.

 

[toobroketoretire]

I Am Really Puzzled

When I reconnected my battery my power antenna tried to rapidly go up and down like it couldn't make up it's mind. But it finally stayed down because it defaults into the down position when the radio is turned OFF. So I have a feeling there is (or was) something going on in my power antenna that was causing the drain. But now the drain isn't there any more and that really has me puzzled. I have been checking my battery voltage every morning and over this past week it has only dropped about 2/10ths of a volt, Do any of you have any idea what was going on and why it quit by removing and reconnecting the fuse?

 

[Antz81]

Without see how it was behaving its hard to say. It could be the antenna as you say. But could also be the relay or the radio itself.

 

[stevolwevol]

I have a drain similar to this on my 77. I tried to find it, then I had my mechanic try to find it. I installed a knife style kill switch on the battery. So when I am not driving it for extended periods, I just reach behind the seat and kill the power. Good security also. I still would like to know what is draining the battery though. It could be the courtesy light back by the spare tire, but I need to take down the tire to find out if it's the culprit.

 

[toobroketoretire]

I have a drain similar to this on my 77. I tried to find it, then I had my mechanic try to find it. I installed a knife style kill switch on the battery. So when I am not driving it for extended periods, I just reach behind the seat and kill the power. Good security also. I still would like to know what is draining the battery though. It could be the courtesy light back by the spare tire, but I need to take down the tire to find out if it's the culprit.

Does your '77 have a power antenna that goes UP when the radio is turned ON? If so try pulling the radio fuse out for a few seconds then stick it back in again. I was fighting my drain for well over a year and by pulling my radio fuse out for several minutes then pushing it back in the drain stopped (???).

I had the cables off my battery and when I reconnected them I heard my antenna trying to power up and down as I was making the connection. So I think the "default" position (down) had something to do with the drain.

 

[Official NOCO]

It sounds like you may need a new battery, or the antenna (or another feature) is drawing too much. We would suggest that you use a replacement battery to see if the issue persists.

 

[toobroketoretire]

It sounds like you may need a new battery, or the antenna (or another feature) is drawing too much. We would suggest that you use a replacement battery to see if the issue persists.

As the battery was almost new I suspected something else was causing the drain. By simply pulling the radio fuse out and putting it back in the drain quit (???).

 

[stevolwevol]

Does your '77 have a power antenna that goes UP when the radio is turned ON? If so try pulling the radio fuse out for a few seconds then stick it back in again. I was fighting my drain for well over a year and by pulling my radio fuse out for several minutes then pushing it back in the drain stopped (???).

I had the cables off my battery and when I reconnected them I heard my antenna trying to power up and down as I was making the connection. So I think the "default" position (down) had something to do with the drain.

I didn't know you asked this till now. I do not have a power antenna, but I still have a 3/4 amp drain. I have resigned myself to it for now, but I have a bug about it, and I am gonna try to find the culprit. I have checked everything I know, but the knife switch on the battery is handy. The worst is when I get in the car, and nothing happens because I forget sometimes to throw the switch. It also comes in handy when I store it for the winter.

 

[Antz81]

I didn't know you asked this till now. I do not have a power antenna, but I still have a 3/4 amp drain. I have resigned myself to it for now, but I have a bug about it, and I am gonna try to find the culprit. I have checked everything I know, but the knife switch on the battery is handy. The worst is when I get in the car, and nothing happens because I forget sometimes to throw the switch. It also comes in handy when I store it for the winter.

Courtesy lights would show up by pulling fuses. But you could still have a problem with headlights, or the altenator that won't show up by pulling fuses.

 

[stevolwevol]

Courtesy lights would show up by pulling fuses. But you could still have a problem with headlights, or the altenator that won't show up by pulling fuses.

I didn't check headlights. How would they drain when they aren't on?

 

[dougelam]

I didn't know you asked this till now. I do not have a power antenna, but I still have a 3/4 amp drain. I have resigned myself to it for now, but I have a bug about it, and I am gonna try to find the culprit. I have checked everything I know, but the knife switch on the battery is handy. The worst is when I get in the car, and nothing happens because I forget sometimes to throw the switch. It also comes in handy when I store it for the winter.

How do you know it's a 3/4 amp drain?

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[Antz81]

I didn't check headlights. How would they drain when they aren't on?

If the switch doesn't open properly when switched off then you could get some current flow. If it's small enough then it won't be enough to make the bulbs glow. Could be a dodgy ignition switch also, which could keep power on to the distributor even after all fuses have been removed.

 

[stevolwevol]

How do you know it's a 3/4 amp drain?

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My mechanic told me, so I'm going by that.

 

[stevolwevol]

If the switch doesn't open properly when switched off then you could get some current flow. If it's small enough then it won't be enough to make the bulbs glow. Could be a dodgy ignition switch also, which could keep power on to the distributor even after all fuses have been removed.

Ignition switch? Interesting you mentioned this. I am not able to turn the key to accessory, so it needs some adjusting. Hmmmm

 

[dougelam]

My mechanic told me, so I'm going by that.

If your mechanic was able to measure a 3/4 amp draw then why didn't he start eliminating 1 circuit at a time to identify the source of the draw?

Relays draw 500 milli amps
Bulbs are well over an amp
Electronics can use as little as 25 milli amps to over 2 amps

The process is not hard, just time consuming
And having a FSM helps seeing what's all on the circuit that you find is causing the draw

If you or him needs more help we can walk you through it

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