M-Class (W166) Produced 2012-2015

Battery Short killed it :-(

Old Oct 6, 2023 | 02:52 AM
  #1  
Terry WM's Avatar
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2002 ML 500
Battery Short killed it :-(

HI ALL

Need some help to start fixing my beloved w166 ml350 2014 bluetech.[img]data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7[/img]
There was an accidental short across the main battery cable that runs to the rear battery.[img]data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7[/img]
Car was running at the time but stopped.

No will turn over but not start - boot wont operate, seats wonts operate, getting active bonnet error, restraint system error.
Looks like an ECU issue or blown power fuse maybe.

Disconnected both batteries and left overnight - no joy
Havnt found an obvious blown fuse yet.

Any help would be very very appreciated really cant afford a dealership.
Any pointers to diagnose to find the fault
Anyone have a star scanner they want to practice with

Please help if you can, desperate me

Terry

Last edited by Terry WM; Oct 6, 2023 at 02:53 AM. Reason: Respect
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Old Oct 23, 2023 | 09:01 PM
  #2  
BACKYARDBODYMAN's Avatar
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ML350 BLUETEC
not sure what fuse could have blown. in caae you didnt know theres another fuse panel next to the battery under the passenger seat. at least my vehicle has a fuse panel there 2012 ml350 blutec. i had to take the passenger seat out to get to it.
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Old Oct 23, 2023 | 11:03 PM
  #3  
Terry WM's Avatar
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Joined: Mar 2013
Posts: 36
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2002 ML 500
Fixed

HI

Yes it was a fuse - learnt a lot about ML350

Boost say they have 3 fuse boxes, in reality they have 7!

The fuse that blew was inside the prefuse box under he floor on the RHS, drivers side in my case. IT was a 150amp fuse that supplies power to the rear.
I had to lift the carpet, and floor cover, then remove the assembly, take it apart, replace the fuse and reinstall, - now all good. ( except playing around I broke the pyro fuse connector in the engine bay, trying to find a new one.).

The fuses are fairly common from electronic stores, Had to do a little ream with a file to open the bolt holes took all of 1 min.

Not the cars fault at all it did the job protecting itself. I connected an Anderson plug near the two bar for an electric winch. The winch had an issue hat blew the fuse. I did have a circuit breaker in line but I think it was a 200amp so the fuse went instead.
I will be downgrading the circuit breaker.
As mentioned learnt a lot, and once you get you head around it, it is not hat complex. So if anyone needs help please yell.





Prefuse box under RHS floor in front of Battery
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