Fuse 11 blowing

3 replies [Last post]
Mon, 25/07/2022 - 14:19
hniblett
hniblett's picture
Offline
Joined: 29.09.2015
Location: Milton Keynes
GWOA Groups: Members

Hi All, 

W460 - 300GD 1988. 

I'm looking for assistance with a fuse that blows as soon as the ignition is turned on. 

Acording to the wring diagram its supplying to the glow plug relay, wiper and reverse light switch. 

I have disconnected all of these, as well as a few other things (alternator, relays, combination switch (indicator stalk) and it still blows. 

So i'm thinknig there is a break to ground somewhere in the wire betwen the fusebox and those components. 

Are there any common trouble points to check first? 

or any other suggestions as to the cause? 

Thanks

Hagar

Top
Mon, 25/07/2022 - 19:11
#1
Jdring
Jdring's picture
Offline
Joined: 12.04.2004
Location: South of Oxford, UK. 87' 230GE SWB Manual, 89' 230GE SWB Auto, 2012 G350Bluetec LWB
GWOA Groups: Committee, Members
Re: Fuse 11 blowing

Hi Hagar (long time since a beer in your 'wine bar').

I think you have nailed the likely issue - a live feed wire has probably worn through on a chassis/body work part.

Check the rear door wiring loom that should be in a corrugated sleeve, but with the continual movement, it always chafes.  

Just thinking out loud here, if it was me... disconnect the live wire at the fuse box.  Check the ignition (it won't blow).  Then run a long wire to each accessible component, just to test them.  Assuming the fuse still doesn't blow on each one, you still have a problem, but maybe one is grounded and you find it?   

Alternatively, get the continuity circuit tester out (or buy one) and test the devices that way, and then work your way along the offending live feed to find where it is earthing.

Others may have a more obvious fix.  Wiring is a bitch.

 

Top
Tue, 26/07/2022 - 14:20
#2
Pistonhead
Pistonhead's picture
Offline
Joined: 17.12.2006
Location: Loughborough
GWOA Groups: Committee, Members
Re: Fuse 11 blowing

Something a miss here, if you have disconnected all components which share this fuse line then the fuse should not blow any longer hence those components you have disconnected are not the culprit. I will have to look and study this more and will see if I can retrive my wiring circuit information otherwise please furnish your full registration number and full chassis no to my email address which I will message over to you. So check your messages.

Top
Mon, 01/08/2022 - 16:31
#3
hniblett
hniblett's picture
Offline
Joined: 29.09.2015
Location: Milton Keynes
GWOA Groups: Members
Re: Fuse 11 blowing

For those who are interested, i have traced the fault to the rear wiper and reverse light. I will do further investigating this week but it looks like a chafed wire in in the barn door conduit. 

Thanks

Hagar

Top