Parasitic loss -- and battery recommendations

Lowell Paddock

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Hoping this august group might have a suggestion as to why I have all of a sudden have a battery-draining parasitic loss. Nothing (electrically at least) has been changed on the car and the battery is about 18 months old. It's run regularly and otherwise starts with no trouble. Any typical trouble areas to investigate?

If worse comes to worse and it's the battery that's bad, is there a somewhat original-fit battery out there? I'd like to have a Varta or some other European type, but they seem hard to find in the US.

Thank you!

Lowell
 

Ohmess

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Hi Lowell -- Not sure I can point you to specific trouble areas, but I will point out that if you seek to narrow down your problem, make sure you take note of the power distribution components of our fuse blocks. If look at this fuse block, unswitched power is distributed across fuses 4 and 5. So when you try to identify parasitic losses when the key is not on, which of course is where you would start to attack this, you need to pull both fuses 4 and 5.

Fuse Block.jpg
 

Markos

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A glove box or trunk light that doesn’t switch off will drain the battery eventually, check these first.
Also, check to make sure you have that little tab that turns off the hood light. Make sure it isn’t upside down also. It should stick up.
 

Arde

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Not so fast! The hood light can be on with the main lights off if the turn signal is left on after shutting down the engine. But only to one side, not the other.

Ahh thanks! The stuff one knows by actually using/driving an e9. :D
 

andyleonard

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Maybe the diode in your alternator died. If you can find a Varta that also is in a VW, the VW dealer has them. I just took a starter battery out of a VW Phaeton that's almost 15 years old. Original battery for the car.
 

jmackro

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If worse comes to worse and it's the battery that's bad, is there a somewhat original-fit battery out there?
It's easy to diagnose whether the problem is a parasitic loss in the car's electrical system or the battery: just fully charge the battery, disconnect it, and wait the # of days that it typically takes for it to run down. If the car will start when you re-connect the battery, then your problem is a parasitic loss. If not, it's the battery.
 
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Lowell Paddock

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Thanks for all the really helpful tips. On batteries, given all the manufacturer consolidation, is there a current good-fitting E9 battery out there? I'm on the East Coast, so no Pep Boys here.
 

adawil2002

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Size is 26R, be sure to secure it properly, not always an easy thing to do, most modern car batteries do not have a clamp foot anymore.
 

E9Wayne

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Lowell, I had a problem like this for many months and wore out a battery chasing it down. It wound up being my"load shedding relay" up above the fuse box. The tailtale was this relay was warm when the car was off. After I removed it, no more problems...
 

HB Chris

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That’s the changeover relay on 73 and earlier coupes, always has switched power, cuts off heater fan when A/C has engaged.
 

Lowell Paddock

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Thanks for all the suggestions. It turned out to be some kind of relay inside of my power antenna(!). I pulled the fuse and the power drain went away. Fortunately, I bought a couple of original Hirschmanns when I was living in Germany in the early Aughts.
 

Ohmess

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Thanks for all the suggestions. It turned out to be some kind of relay inside of my power antenna(!). I pulled the fuse and the power drain went away. Fortunately, I bought a couple of original Hirschmanns when I was living in Germany in the early Aughts.
I love that we all find it perfectly normal that someone would purchase a couple of backup power antennas.
 

sfdon

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Available from the dealer cheaper than other batteries from car parts stores.
 
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