W211 shorting to body at F32
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Mercedes w211
W211 shorting to body at F32
Hi all,
I have a 2004 w211 and have been using MBW to search a problem with battery drain. After lots of tests, fuse and relay pulling I have finally homed in on the F32 prefuse box.
It took an age to find, as all documentation says its in passenger foot well, but on RHD cars it is in driver footwell and difficult to access.
When I disconnected all the outgoing cables from the F32 prefuse box the drain continued, until I disconnected the main cable from the battery. Then the drain stopped.
Clearly, something is wrong with it, However, even following the MB workshop directions to remove the box it remains fastened to the bodywork.
So does anybody know how to remove it? The big stud that connects to the battery appears to go right through the box (looking at pictures of replacements) but if it does
and is shorting to the bodywork, then I think that will be my problem.
As supporting evidence of this; if I disconnect the negative side of my battery under normal conditions there is a potential difference on my voltmeter between the negative post
and the body work and the ammeter shows 0.180 amps flowing.
Also when I have disconnected the positive cable on the F32 prefuse box and test for resistance between that post and the bodywork there is a conductivity.
All this points to a short somewhere. somehow within that F32 box. But I need to get the damned thing off and I just can't!
How it is attached to the body??
Anybody know??
Thx.
I have a 2004 w211 and have been using MBW to search a problem with battery drain. After lots of tests, fuse and relay pulling I have finally homed in on the F32 prefuse box.
It took an age to find, as all documentation says its in passenger foot well, but on RHD cars it is in driver footwell and difficult to access.
When I disconnected all the outgoing cables from the F32 prefuse box the drain continued, until I disconnected the main cable from the battery. Then the drain stopped.
Clearly, something is wrong with it, However, even following the MB workshop directions to remove the box it remains fastened to the bodywork.
So does anybody know how to remove it? The big stud that connects to the battery appears to go right through the box (looking at pictures of replacements) but if it does
and is shorting to the bodywork, then I think that will be my problem.
As supporting evidence of this; if I disconnect the negative side of my battery under normal conditions there is a potential difference on my voltmeter between the negative post
and the body work and the ammeter shows 0.180 amps flowing.
Also when I have disconnected the positive cable on the F32 prefuse box and test for resistance between that post and the bodywork there is a conductivity.
All this points to a short somewhere. somehow within that F32 box. But I need to get the damned thing off and I just can't!
How it is attached to the body??
Anybody know??
Thx.
