I had a new modern ignition system in my 1974 installed several months ago and the battery draws down on a hit or miss basis after living the car overnight. the shop that installed the system told me that this could not be causing the problem without really checking and seems clueless regarding the problem.

 

For there to be a significant draw down on the battery in an overnight period the load would also have to be significant. The clock will flatten the battery, but it takes quite a long time.

If you were to disconnect the clock, about the only item on an S3 E Type that will will be on when the ignition is turned off, and check for continence with a multi-meter across disconnected battery leads, this will indicate if any circuits are closed. By a process of elimination involving disconnecting suspect items, you will discover the source of the draw down.

Regards,

Bill

 

An easy way to determine where the problem is would be to use a multimeter in amperage or current mode in-line with the battery, then start pulling the fuses one by one until the current draw stops. Also try disconnecting your new ignition system to see if that is pulling any current.


HTH,
Steve

 

Thanks Steve, since this happens on an occasional basis and by the time I find out the battery is already dead so I sent the car to the shop to see if they can get a handle on this. I'll post what they find