SL/R230: Battery Drain by Adjustable Steering Column?
Thread Starter
Member
Joined: Jan 2006
Posts: 124
Likes: 9
From: Michigan
2005 SL500, 2022 GLS 450
Battery Drain by Adjustable Steering Column?
I have a 2005 SL500 that lately has been having issues with trunk battery not staying charged. Battery itself is newer and ok. There is a current draw of 1.7A while the car is asleep. After pulling every fuse/relay in the car the only one that had a big impact was the 7.5A fuse in the trunk that is right next to the battery (F78 according to fuse diagram). Current draw drops to about 0.2A after pulling this. There seems to be three modules associated with this fuse:
1. Adjustable Steering Column
2. Engine Control Unit
3. Engine Emergency Stop
Everything in the car works, no faults, no noises while the car asleep. Does anyone know if there is an easy way to gain access to the adjustable steering column wiring harness to unplug to see if that is the issue? I'm not even sure where it is. I'll check the engine control unit too, if I can find it. No idea what the engine emergency stop is...maybe tied to keyless go which I do have?
1. Adjustable Steering Column
2. Engine Control Unit
3. Engine Emergency Stop
Everything in the car works, no faults, no noises while the car asleep. Does anyone know if there is an easy way to gain access to the adjustable steering column wiring harness to unplug to see if that is the issue? I'm not even sure where it is. I'll check the engine control unit too, if I can find it. No idea what the engine emergency stop is...maybe tied to keyless go which I do have?
Thread Starter
Member
Joined: Jan 2006
Posts: 124
Likes: 9
From: Michigan
2005 SL500, 2022 GLS 450
It was determined by myself measuring current draw while removing fuses one by one. Removing fuse F78 causes current draw to drop to 0.2A. then 0.1A after some additional time. According to fuse diagram, F78 feeds the three units mentioned in my original post. I did find the engine controller and that was not the source of the draw.
I now see that adjustable steering column is covered by three fuses, would be nice to see an actual wiring diagram to see what F78 is actually powering in the steering column.
Still not sure what Engine Emergency Stop is, but doubt this is the source.
I now see that adjustable steering column is covered by three fuses, would be nice to see an actual wiring diagram to see what F78 is actually powering in the steering column.
Still not sure what Engine Emergency Stop is, but doubt this is the source.
Thread Starter
Member
Joined: Jan 2006
Posts: 124
Likes: 9
From: Michigan
2005 SL500, 2022 GLS 450
Thread Starter
Member
Joined: Jan 2006
Posts: 124
Likes: 9
From: Michigan
2005 SL500, 2022 GLS 450
I think I found the problem. The lever for adjusting steering column was stuck on for some odd reason. Just barely touched it and jumped back to neutral position. Current draw drops down to 0.02A after everything goes to sleep now.
