Battery Drain Question

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Sebastian Gaeta
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Location: Ann Arbor, MI

Battery Drain Question

#1 Post by Sebastian Gaeta »

Greetings,

On my 1964 C cab my battery will go dead if sitting for more than a week. I did a draw test with test light grounded and then placed onto negative post with ground cable removed and key shut off. One by one I pulled each fuse and the light did not go out on any circuit! I do not have an amp meter at home to test for a drop so could only use the test light.

Scenario:

Recent work before symptoms arose: Converted my 022 distributor back to points from Pertronix, Ignition switch removed, rebuilt by Dick Weiss and then reinstalled by me, regular maintenance (oil change, valves etc but nothing else associated with electricals).

Other items of note: Battery is a brand new Optima, wipers don't work but they stopped last year and the car did not drain the battery last year and I just have not gotten around to fixing it. All fuses were good except #2 but I don't know why that would have popped because I don't have a fresh air blower or gas heater etc.

Thoughts?
Sebastian Gaeta
www.arbormotion.com

Registry #8339

'65 C coupe
'64 C cab

-------
2014 Boxster 981
2005 997 C2 Cab
1967 Karmann Ghia Convertible
1966 VW Single Cab
1966 Ducati Cafe Racer
1964 Karmann Ghia Coupe
1963 Beetle

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Thomas Sottile
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Location: Stamford CT
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Re: Battery Drain Question

#2 Post by Thomas Sottile »

Get yourself a cheep electrical meter. 15 bucks

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Sebastian Gaeta
356 Fan
Posts: 3047
Joined: Tue Mar 25, 2008 5:50 pm
Location: Ann Arbor, MI

Re: Battery Drain Question

#3 Post by Sebastian Gaeta »

Thomas Sottile wrote:Get yourself a cheep electrical meter. 15 bucks

Thanks Tom, I do have one but as I said just not at home and I am hoping to resolve this issue today.

EDIT: I guess what I want to know is that when the light does not go out when pulling all ofthe fuses (one at a time) where do you look from there? In know a meter will tell me where the drop is, but does anyone have suggestions for doing it with just a test light and the light not going out?
Sebastian Gaeta
www.arbormotion.com

Registry #8339

'65 C coupe
'64 C cab

-------
2014 Boxster 981
2005 997 C2 Cab
1967 Karmann Ghia Convertible
1966 VW Single Cab
1966 Ducati Cafe Racer
1964 Karmann Ghia Coupe
1963 Beetle

John Rowell
356 Fan
Posts: 5
Joined: Mon Jul 31, 2017 5:03 pm

Re: Battery Drain Question

#4 Post by John Rowell »

Hi, this worked for me once: Disconnect the battery (make sure it's charged) and remove all the fuses, with the ignition key off. Then re-connect the battery ground. Touch the positive battery cable to the positive post (no need to actually connect it). There should be no spark when you do this, indicating nothing is draining the battery. Then one by one install a fuse and touch the cable as before. If you see a spark (often very small) that means that circuit is using battery power when the ignition is off, thus draining the battery.

If when performing the initial step with all the fuses removed you see a spark, it could be an internal short in the alternator (which you don't have, but maybe someone else would know if the generator could cause this) or something is unfused and connected such as a channel saver for the radio/stereo (again which you don't have, unless something modern is installed in your car). Hope this helps a bit.

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Sebastian Gaeta
356 Fan
Posts: 3047
Joined: Tue Mar 25, 2008 5:50 pm
Location: Ann Arbor, MI

Re: Battery Drain Question

#5 Post by Sebastian Gaeta »

Thanks so much John, I will try this and report back.
Sebastian Gaeta
www.arbormotion.com

Registry #8339

'65 C coupe
'64 C cab

-------
2014 Boxster 981
2005 997 C2 Cab
1967 Karmann Ghia Convertible
1966 VW Single Cab
1966 Ducati Cafe Racer
1964 Karmann Ghia Coupe
1963 Beetle

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David Jones
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Tag: I wish I knew as much as I think I know.
Location: Kentucky

Re: Battery Drain Question

#6 Post by David Jones »

Sebastian, disconnect the wiper motor via fuse #4. It is possible that the cam is not opening the points far enough to properly isolate the wiper motor field coil and that is causing a parasitic current draw.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715

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Sebastian Gaeta
356 Fan
Posts: 3047
Joined: Tue Mar 25, 2008 5:50 pm
Location: Ann Arbor, MI

Re: Battery Drain Question

#7 Post by Sebastian Gaeta »

David Jones wrote:Sebastian, disconnect the wiper motor via fuse #4. It is possible that the cam is not opening the points far enough to properly isolate the wiper motor field coil and that is causing a parasitic current draw.

Thanks David, would this still apply even though the test light stayed on when I pulled the #4 fuse?
Sebastian Gaeta
www.arbormotion.com

Registry #8339

'65 C coupe
'64 C cab

-------
2014 Boxster 981
2005 997 C2 Cab
1967 Karmann Ghia Convertible
1966 VW Single Cab
1966 Ducati Cafe Racer
1964 Karmann Ghia Coupe
1963 Beetle

User avatar
Sebastian Gaeta
356 Fan
Posts: 3047
Joined: Tue Mar 25, 2008 5:50 pm
Location: Ann Arbor, MI

Re: Battery Drain Question

#8 Post by Sebastian Gaeta »

OK, I did what John suggested and without any fuses I touched the positive cable to the positive post and I heard a click. It sounded very familiar and I remembered I left something off the list of work just done. I replaced the steering column bushing and had the turn signal switch disconnected (kind of a big one to forget, I know).

The clicking I heard sounded just like pulling back on the switch to flash the high beams, so I imagine that is where I will start.

Thanks to all, and especially John Rowell for the suggestions.
Sebastian Gaeta
www.arbormotion.com

Registry #8339

'65 C coupe
'64 C cab

-------
2014 Boxster 981
2005 997 C2 Cab
1967 Karmann Ghia Convertible
1966 VW Single Cab
1966 Ducati Cafe Racer
1964 Karmann Ghia Coupe
1963 Beetle

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Mike Wilson
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Joined: Tue Apr 15, 2008 4:37 pm
Location: SW Los Angeles

Re: Battery Drain Question

#9 Post by Mike Wilson »

I had a t/s switch stick on the high beam flash for a bit. That just might be the problem. Let us know!

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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Sebastian Gaeta
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Posts: 3047
Joined: Tue Mar 25, 2008 5:50 pm
Location: Ann Arbor, MI

Re: Battery Drain Question

#10 Post by Sebastian Gaeta »

Update: I isolated the clicking noise to the ignition switch. I also have Tony Euganeo's starter relay behind the dash. Note, this is not the one that Joe Leoni designed to go on the starter, but is behind the dash next to the ignition switch- http://www.lockandkeyid.com/surestartrelay

When I reinstalled the ignition switch after Dick Weiss' rebuild, I incorrectly placed the black wire from the relay as I did not have the instructions anymore, but the car cranked and started so there was no need to dig into it any further.

I went on Tony's site, looked up the the instructions and corrected the wiring. The click was now gone when connecting the battery ground and touching the positive cable to the positive post. The car cranked and fired right up!

I have not buttoned it up yet but will do so and report back if i find anything else, but if not thanks to all for the help.
Sebastian Gaeta
www.arbormotion.com

Registry #8339

'65 C coupe
'64 C cab

-------
2014 Boxster 981
2005 997 C2 Cab
1967 Karmann Ghia Convertible
1966 VW Single Cab
1966 Ducati Cafe Racer
1964 Karmann Ghia Coupe
1963 Beetle

User avatar
Mike Wilson
Classifieds Monitor
Posts: 11492
Joined: Tue Apr 15, 2008 4:37 pm
Location: SW Los Angeles

Re: Battery Drain Question

#11 Post by Mike Wilson »

Success! Way to go!

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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Charles H Jacobus
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Posts: 493
Joined: Wed May 28, 2014 5:02 pm
Location: Dallas, TX

Re: Battery Drain Question

#12 Post by Charles H Jacobus »

Congratulations, nice you were able to talk it out.

Chuck
Current:
2012 Silver 991
1995 Midnight blue 993
1965 Red 356C

Past:
Fond memories of 14 others (including a '63 Normal and a 61 S90) :)

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