Battery drain

[benchracer1]

I have a 69 bug with an alternator conversion that I inhereted from my dad. He would leave a battery tender on it to keep a charge. I am now trying to troubleshoot it. I’ve put a multimeter in series between the neg terminal and cable. I pulled the fuses one at a time and the reading never changed. I’ve visually checked the wiring and found no problems. I even disconnected the radio. Anybody got any ideas. If I let the car sit for a week it has to be jumpers….Steve

[Cusser]

I suspect the ALTERNATOR. It may charge fine, but likely a source of your parasitic drain.
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[bsairhead]

With a cable off (makes no difference which one) monitor the battery voltage for a few days.

[runamoc]

[Cusser]

Disconnect the main wire to the alternator, and see if the battery drain stops.
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[benchracer1]

I tried disconnecting the alt wire. Made no difference

[bsairhead]

Have you verified it's not the battery?

[benchracer1]

She has a relatively new battery. It was happening with the old battery as well

[bsairhead]

With the battery disconnected from the system hook your meter between the cables on ohms. Try pulling fuses to see if you can drop the resistance. I like checking for drains this way as I can wiggle the keys and open and shut the doors pull fuses and play with all the switches without fear of shorting anything.

[runamoc]

[benchracer1]

I'll do that this morning

[ashman40]

[benchracer1]

[talljordan]

7ma of parasitic drain is likely normal and nothing to worry about. That's practically nothing. A typical car battery carries 40,000+mah of power.

You'd have to not drive the car for 6 months or more to drain the battery at that rate.

If you aren't driving for a whole season, you should be disconnecting the battery regardless.
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1972 Super Beetle, Parked until adequate restoration funding is acquired in restoration!

Wanted: Male computer diagnostic plug end

[volksworld]

you could be chasing the wrong issue....you may have a starter situation where the solenoid wont engage with "normal" battery voltage and keeping it on the tender gives it just enough more...if it wont start, jump across the solenoid from the battery cable nut to the push-on spade terminal with a screwdriver and see if the starter cranks (all safety precautions of course)...if it does, but wont crank via the key, time to either install a "starter booster relay" and/or go down the rabbit hole of why isnt it getting enough amperage to start...corroded connectors. chassis grounds, battery cables, internal wire resistance ,bad starter or switch etc....its a very common issue because of the length of wire involved going from the battery up to the key and all the way back to the starter again....a battery load tester will show if the battery is strong enough to start the car...perhaps you could get a free loaner from a local parts chain or just bring the battery to them (out of the car) for them to test it...7ma is nothing...you'd be seeing like a half an amp or more to have a problem

[ashman40]

[benchracer1]