Dazed And Confused

[calliebrat]

Hey Everyone!

I haven't been here in a while but I need some suggestions.

I have a 1975 280 Z that something keeps draining the battery.

We have tested the battery- not it, we purchased a new voltage regulator- not it, we have not a clue as to what is pulling the power from the battery.

Have checked wire from ignition switch to the transistor unit with the ignition off and to the coil and there is no electrical drain there. Have checked the light switch in the same way and there is no drain there.

We have charged the battery up full and have left it un hooked and then checked it 12 hrs later and it still had a full charge.

Then hooked up the battery& bout 2 hrs. later- put the charger back on& it is taking 10 amps showing that the battery was discharged just sittibng.

If anyone has any suggestions as to what the problem might be please respond. Thanx,

Stacey & Michael

'74 260 Z Coupe

'75 280 Z Coupe

El Cajon, CA.

"Drive Fast- Take Chances"

[kenz240z]

If you have a digital multi-meter, it would assist you in trouble shooting the battery drain problem you are having. Set the multi-meter to measure current (amperes). Disconnect the positive cable from the battery and connect the + lead of the meter to the positive battery post. Connect the - lead of the meter to the positive battery cable.

The meter should display the current drain on the battery in amperes. Now, disconnect one electrical connection at a time and watch the reading on the meter. When you find one where the reading goes to zero you have found the circuit that is causing the drain.

Once the offending circuit has been identified you will have to trouble shoot further to find out what the problem is. Most likely it is a short in the circuit somewhere, meaning that either a conductor (wire) or a device in the circuit is making a connection to the body somewhere, thereby completing an electical circuit and causing the drain. :mad:

Be careful when tracing the bad circuit out, because there could be a fire hazard. If a small, un-fused wire is shorted to the body the amount of current through it could heat it up to the point where it will get so hot that the insulation will burn off. :eek:

I would suggest having a helper ready to disconnect the meter from the battery to cut off power to the car if that happens.

Best of luck!

Kenny P.

[calliebrat]

Kenny,

Thanx so very much for the advise. Right now I'd try just about anything. Just joking.

We all know how frustrating it can be.

Will let you know if that was the problem or I'll be here with another discription of whats going on. Thanx, Stacey

[Jayru]

I'm having the same problem, only it takes 2 weeks for my battery to go dead. I can't seem to find a drain anywhere. Is it so small that it won't even register on an amp meter?

Is there a common slow drain on these cars?

[jmark]

I bought a Battery Tender Jr. for all my Z's. I don't drive them every day. It maintains the proper charge then shuts itself off and monitors the battery. Great product and reasonable $.

http://www.batterytender.com/

I bought two from Ebay from this guy jay6712 for a Buy it Now price of $18. Great price & shipped fast. They are $32 at Pep Boys.

[MikeW]

I've used a similar troubleshooting approach. Instead of hooking the meter up at the battery it's much quicker to do it at the fusebox. With everything in the "off" position simply remove each fuse one at a time and bridge the gap in the fuse box with the meter set for current. With everything off there should be no current flowing so any reading at all indicates a drain. I can't remember if the clock gets power through the fusebox so that might be one exception.

[dogma420]

""Is there a common slow drain on these cars?""

No there isn't. I have a pretty good battery in my car; due to hot weather I'm not driving it much; when I redid the gas tank, I didn't start it up for a full month, no problems--started no problem, a couple more cranks than normal due to sitting so long, but no problems. No drains--they aren't normal, just like any other car. The clock doesn't use much of anything (also presets in radio).

[EScanlon]

There CAN be a slow drain that wouldn't necessarily register through the fuse box. I had it happen when the Accessory Relay went bad on me.

The easiest way is as Ken pointed out. Except I use a small continuity checker in line on the negative side of the battery. (By the way, to check for a drain, either the negative or positive will do.) As long as the bulb is glowing (and the rate of glow indicates the size of the drain) there is a drain. Disconnect items and if no change then reconnect them. This ensures that you don't introduce other problems. Check the relays on the kick panel, these have been known to go bad and cause your symptoms.

Enrique