Speedtoys

Seen much debate on this, What should my parked & off drain current be? Chasing down either a weak battery or a drain while parked. thanks

StratfordShark

Something of order of 25mA or so. Low enough for a charged battery to go for weeks and still happily start the car

polecat702

The clock in my radio will drain the battery in a month or so. I just disconnect the battery when I'm outta town working.

dr bob

Jeff --

My '89 drains at about 20mA. I have an aftermarket radio (Blau Alaska), no additional amplifier and the original one removed. Otherwise, it's as delivered. Do you have a meter you can use to determine the actual drain current?

Meanwhile... Charge the battery with whatever charger you have. Once it's fully charged, let it rest for half an hour, then use a handy specific-gravity tester to determine the remaining real capability. The little floating-ball testers are a couple dollars at WalMart in the battery electrics rack in automotive. Your POLAPS will have them too I'm sure. Simple and easy test.

Heat is a battery's enemy. 150º For curing paint is deadly, in my limited experience. It took a few painting "episodes" to figure out that the battery leaves the paint shop with me when I drop the car off.

Randy V

Thread title fail...

dr bob

FIFY...

Ducman82

20ma or less is common. how long is it taking to drain?

SeanR

Anything under 50ma is acceptable. Mine sits around 40ma and lasts for over a month just sitting.

Ducman82

had had to find a drain that was about 4 amps... LOL. turns out the "interior installer" destroyed one of the passenger seat switches (early car) and the "lift" motor was stuck on.........

SeanR

The day my car was delivered the owner had warned me about how the battery wouldn't stay charged for very long. So I was sitting in the car in a quiet garage and could hear a faint "thud" that was constant. Ended up being a bad passenger switch doing the same thing. Unplugged it and drain was gone.

jheis

Yeah, nothing "quick" about parasitic drain questions....

Jeff777

Guys,

Thanks for the info. My battery drain continues. Here's what I've done so far:


1. Alternator pulled and checked and voltage regulator replaced as precaution.
2. Transistor replaced on CCU(draw was around .47 amps.) Transistor was defective.
3. Battery replaced.

For awhile the drain was .06 amps but the problem returned. Here’s what I have today following your procedure:

First Battery drain .36 amps
Pull fuse 1. .02 amps
Put fuse 1 back in. .065amps....why not back to .36?

Ignition On(1sec) .7 amps
Off. .30 amps

Did another parasitic drain test and got around .06, not too bad. This would not drain the battery in a few days. But when I checked 30 minutes later it was back up to .37. How can this be? Somehow I think the CCU is turning something back on. Door switches check out and all the drain seems to disappear when pulling fuse 1.

I have used the T OBD and ran the test outputs on the CCU, all seem ok. Can't get the trouble codes sorted out yet(another problem). I think the next thing is to pull the CCU unit out and see if the battery still drains.

Any thoughts?

Thanks

Speedtoys

Tested it all, in the end it was a batter that just..instantly was no good.

dr bob

It Helps Tremendously If We Know What Year Car You Are Working On. [not as loud as SHOUTING but bigger than a mumble...]

Some hints as you chase parasitic drains:

-- Reminder that you need to fix or otherwise eliminate drains while and immediately following door-open events.

-- There safety and device relays related to window motors and sunroof that can stay active for a period following key-off.

-- Some "leaky" controllers will show a drain after they are shut off, but that drain stops if you disconnect and reconnect power. That means you need to do any in-series measurements without actually disconnecting the load. Put your ammeter leads on a ground point in the back, other on the battery negative post. Only then, lift the battery ground strap connection at the rear apron.

-- A fuse is a resistance in the current loop to a client device. You can use your DMM with some needle probes to read the voltage drop across a fuse in service. The fuses have tiny test openings at the ends of the exposed face. Put one probe in each end and measure millivolts with your meter. More voltage drop means more current is flowing. There are a few internet-published guides that include some translation from fuse sizes and voltage drop to help interpret your readings, but I'm not sure they are really very accurate. Better to use them to identify possible leaks, then focus a better inspection when you have a circuit that's suspect.

-- My parasitic drain "toolkit" has a small 12V light bulb with spade-ended test leads on it. Plugged into a fuse socket, the lamp glows when current passes through that circuit. It's not perfect but it's a handy filter to include in a loop to get instant indication of a larger drain. The kit has a cool little clamp-on DC ammeter that reads milliamps too.

Jeff777

Sorry....1992 C2 964