[W126 Coupe] Long Term Problem

[Vance Rowley]

To cut a long story short regarding my intermittent 6amp peak battery drain. Today, I checked many things including the relay "K" (it's not there) all the fuses that are listed "hot at all times" (made and tried the 1amp fuse test ) except one. That is fuse number 3. This fuse is hot all the time and feeds the rear screen heater. As this is a 30Amp bolt on fuse, by the time I had tested everything else, it had gone dark and cold.

Apart from this fuse, everything is pointing to my Meta Alarm system, namely the backup battery which I guess has had it, and maybe the system is intermittently trying to charge the backup battery for the alarm from the main battery which is probably knackered. (the backup that is, not the main).

Question is, does anyone know where the alarm backup battery is located? I can't find it. Is it inside the car, or under the hood somewhere? I would have thought the latter, but no luck yet. Obviously I didn't install the alarm system and I have been in touch with the place I purchased the car from, but they don't deal with the company anymore that used to fit the alarm/immobilizer systems for them.

I recon if I could find this backup battery, test it and prove a cell or two is gone. Replace it (once I have found a source for them) I think this 5 year problem could be solved .

I appreciate any info.
Cheers,
Vance.