Where to attach the negative terminal on a 85-911

[69porsche]

I have a 85-911 stock. Lately my battery has been draining, I think because of the radio system that I need to eliminate. My question when charging a battery ( I am using a CTEK charger) on what part (photo's would be nice) do you place the negative terminal. I am charging the battery within the car NOT outside......I see and read to attach it to some solid, etc, not sheet metal, etc......Where do you attach your negative terminal when charging the car or if you have to jump it. Thanks in advance!

[john walker's workshop]

On the negative post? The whole steel chassis is ground, so lots of options.

[76FJ55]

For charging; Red to positive post, black to negative post of battery

For jumping it is suggested not to connect to negative bots as there is the potential to have hydrogen gas in the area of the battery and jumper cables could cause a spark igniting the hydrogen.

When using a charger, the leads should be connected to the battery before the charger is plugged in. Since the charger isn't energized while the leads are being attached, there should be no potential for a spark.

[KTL]

You might have a drain due to the power window relay. If you can believe it, these old cars have a key-off power feature that allows you to raise the windows after the ignition key is turned off. The power window relay is connected to the door switch to accomplish this. So be sure to check that your door switch is not hanging closed because the switch needs to open when the door is open in order to break the feed to the power window relay.

But, yes, radio hacks usually do cause this problem.

[69porsche]

Thanks all-All good advice!

[darrin]

Originally Posted by KTL

You might have a drain due to the power window relay. If you can believe it, these old cars have a key-off power feature that allows you to raise the windows after the ignition key is turned off. The power window relay is connected to the door switch to accomplish this. So be sure to check that your door switch is not hanging closed because the switch needs to open when the door is open in order to break the feed to the power window relay.

But, yes, radio hacks usually do cause this problem.

great suggestion -- if your interior (dome) light isn't working and your power windows work when the driver's door's open, you've likely found your culprit