Ls 400 Kills Batteries

[mmV8]

Hi Guys,

My 98 model LS400 has a current Drain issue I can't trace. If not driven for more than 3 days, the battery will be flat. Last time I checked, and removed all the main fuzes- it was still pulling 300mah. I check to make sure all the interior lights are off at night, and I don't even lock it so I guess the alarm is not activated.

Does anyone have any ideas ?

Also : radio lights - does anyone know if they are replacable mine have never worked. Chasing a drivers side mirror glass.

[LEX51S]

Hi Guys,

My 98 model LS400 has a current Drain issue I can't trace. If not driven for more than 3 days, the battery will be flat. Last time I checked, and removed all the main fuzes- it was still pulling 300mah. I check to make sure all the interior lights are off at night, and I don't even lock it so I guess the alarm is not activated.

Does anyone have any ideas ?

Also : radio lights - does anyone know if they are replacable mine have never worked. Chasing a drivers side mirror glass.

bit late im guessing but you may have a broken cable somewhere to do with the radio lights not working and that could be draining your battery.

[Greavett]

I've had the key inserted switch in the barrel for the ignition cause a drain before. Thinks the key is inserted and keeps voltage applied to accesories etc.? Does your steering wheel retract all the way when key out or even extend when key inserted? Other way is to fit your ampmeter and remove each fuse/relay in turn to see which circuit your draw is related to! Once amps drop you know you've found it!

Two other possible causes both of which i've had in the past also. The alternator could be faulty, draining battery off. Had customer complaints of Range Rover doing the same thing. Came to the dealer four of five times for flat batteries, could never find the drain. Then by chance one trip, noticed a bit of a spark from the alternator.

The other thing that I've had which was rather hard to find was a battery hold down clamp draining the battery. To check get a multimeter and with the negative lead held on the earth terminal, slowly run the positive lead across the battery. If your getting any voltage at all, then your batteries casing is leeching and therefore applying voltage to your clamp. It will only be small, not enough to cause sparking/arcing but will drain battery very quickly. Hard to find that one, and caught a few people out before it came to the shop.

With the alternator, remove the main lead from it and see what amperage draw you have then.

Simon