Anyone have this battery problem? (1 Viewer)

[option13]

Here's the problem:
My '94 doesn't get driven much, it only has 70k miles on it.
I recently replaced the battery because it was 6 years old and kept dying on me unless I drove it everyday.

I thought the new battery would fix the problem, but now after not driving it for a week the new battery is dead. I jumped it off and noticed I hadn't lost the presets on the radio and the time on the clock was correct (shouldn't I lose the presets?).

I drove to Advance Auto and had them connect to my LC and test for a drain but they found no problems.

Anybody else had this problem?

Thanks,
Rick (option13)

 

[george_tlc]

YOU must measure the current draw from the battery while you 80 is just "sitting" in its normal off position. I wouldn't trust the readings from some chain parts store.

You need either a low current reading Clamp on DC current meter or a Multimeter on the Amp range. Take the measurements with everything OFF just as you would have normally with the 80 just "sitting".

For a battery to run flat in a week means you are drawing too much current. Could be an wonky alarm or something else drawing power. Searching this site would likely find you some test procedures and isolation procedures - which basically involve then removing fuses to determine which 'branch circuit' is drawing the current.

The radio will likely store presets even with only 8V or less - way too little to start the vehicle, but plenty for the radio.

Anyhow, YOU need to take measurements and report back.

Even 200mA current draw (which isn't a lot) would draw the battery down over time. Consider 200mA or 0.2A for 24 hours would draw 0.2 x 24 = 5 A.hr. Do that for a week and you've drawn 5 x 7 = 35 A.hr from your battery. If you then only drive to the corner store and back you will NOT have put that 35 A.hr back into the battery. Repeat the next week and you've now drawn down a further 35 A.hr and your battery is now dead flat...

Take some measurements. Multimeter on the amps range goes IN SERIES with say the ground connection to the battery, i.e. you will need to remove the ground lug from the battery to measure, UNLESS you have a DC current clamp.

cheers,
george.

 

[option13]

Thanks for the input george_tlc!!

I traced the power draw to the driving lights(actually the rear stop lights at the rear sides of the vehicle) when I turned the driving lights off .....no power draw. This is good. However, I believe that even with the driving light switch in the on position, turning the key off should kill the power. Am I wrong?

Rick(option13)

 

[shermantank55]

light switch power drain

I had the same problem with a 105 series. Even with ignition off and key out, with the light switch on the power would trickle out, killing the battery in a few days. Took awhile to figure that out, so if I just rotated light switch off, the battery would keep a charge. Never traced the problem further, just shut off the light switch.

 

[george_tlc]

Thanks for the input george_tlc!!

I traced the power draw to the driving lights(actually the rear stop lights at the rear sides of the vehicle) when I turned the driving lights off .....no power draw. This is good. However, I believe that even with the driving light switch in the on position, turning the key off should kill the power. Am I wrong?

Rick(option13)

On our '97 that if you have the light switch ON and turn off the ignition it keeps the lights turned on for a while. There's obviously some "smarts" (read electronic junk) that is in that path and it DOES consume extra current to do its "magic". This is fine if you are just parking the vehicle for a few hours etc., but obviously not a good idea long term.

Turn OFF the light switch rather that relying on the "smarts"....

cheers,
george.

 

[Bob_Garrett]

If I remember correctly, the owners manual on my 95 recommends turning the light switch off if leaving the vehicle parked for an extended time.

 

[option13]

Thanks for the help guy's. I'll start turning the lights off when I park it. I sure am glad it was something that easy.

Rick(option13)