Am I just stupid ? - was 'Electrical fault - body live.. scratching my head '
Having put the body back on, one of my next tasks was to upgrade all of the existing multi-way connectors to Weatherpacks, which I completed las week - all are fine and tested out OK.
What isn't right is that when testing I discovered I have a potential difference between the body and earth! I suspect the leakage is fairly small and having spent some time on it today, I have determined that it is the circuit serviced by fuse 8 that has the problem (continuity test between the feed from the battery and chassis demonstrates this - remove fuse 8 and continuity is broken.
Fuse 8 on my 300GD covers Courtesy Lights, Door contact switch and heated rear window.
Disconnecting the feeds to the rear of the vehicle (which includes the heated window) doesn't solve ot, which meas the problem is likely in the dash.. Helpful in the I've got the dash out at the moment to do the blower, unhelpful in that its difficult to trace!
Anyone had any experience that is similar? Just wondered if there was a commong place that rubbed through of failed?
Hi
From a novice DIY repairer i would say that you are "not stupid" as any electrical issue is usually a nightmare to identify even if you use a methodical approach to diagnosis.
My last 20 years of restoring 20 - 40 year old vehicles has thrown up many of these frustrating problems that usually ends up placing the fault on an earth connection, either caused by freshly painted body / chassis causing poor contact or a rusty / corroded connection caused by water ingress.
I guess there is also a possibility that you could have connected something back up the wrong way around after having the body off, especially if you have changed some or all of the multi plugs?
It should not be a huge task to trace each of the circuits that run through that fuse with a circuit tester even if you may need another pair of hands to help.
I have never heard of any "problem" areas on the G however i am not looking at these vehicles for a living . The only person i can recall having any such issue was a member called kick can hengel, who runs a couple of 460 300GD's i think. He recently had an electrical issue behind his dash causing a small battery drain that was enough to flatten the battery over a weekend. It was a simple fix as i remember as most of these are in the end but you would be better off to PM him for an exact cause and effect.
Hope you get sorted
Gav
Sorry
Was posting that while you were posting your fix!!!
Gav
JOIN THE GWOA
This website and forum are provided for the benefit of enthusiasts and owners of all Mercedes Benz off road vehicles, in particular the G Wagen. The costs of development, upkeep and provision of the site are met entirely by the annual subscriptions of club members. If you are using the site and are not a member of the G Wagen Owners Association please consider joining. You will have access to areas on the site that are not open to non members, to club trips and meetings and to technical assistance. In addition your contribution (only £25 annually) will help us maintain and develop our website for future users.
Who's new
- Jaffa_JIM_23
- Wrabstar
- GG
- KTMSCANIA22
- 280ge
So, line by line I worder through with the continuity tester this morning.
I finally narrowed it down to the courtesy light in the rear, with the red/yellow feed from fuse 8.
Continuity was showing between the body and this feed. It was then that I noticed that the courtesy light was switched to the permanently 'on' position. .
So with courtesy light on we have continuity and a PD of 13v between -ve terminal on battery and body, off and the circuit is broken consequently no voltage.
It was then that I noticed I had forgotten to bolt on the earth to the battery compartment.
So unless I am being thick about this, actually everything is as it should be.
Still, the back of my dashboard and wiring loom is nice and clean now