W211 Electrical faults

[E270 Owner]

Electrical Faults list.

Full red dash screen with battery icon & visit workshop.

No wipers
No indicators
No headlights
No windows
No horn
No hazards
No heated seats
No rear blind
No heater motor
No fuel gauge
No central locking

And a few more I cant remember right now.

:0

Any ideas/guesses before I start on it tomorrow ?

 

[Deleted member 37751]

Alternator?

 

[E270 Owner]

Battery & alternator are new and tested correct.

 

[Deleted member 37751]

SBC pump?

Gets blame for everything else.....

 

[merc85]

Are both batteries ok?

 

[E270 Owner]

If the small SBC battery was faulty I would expect SBC errors like no SBC hold etc, but all is ok there.



I have more info regarding errors
Dash readout shows

ESP fault
Instrument cluster fault

Just been told ............

 

[HB]

I had this. New batteries ,new alternator and all sorted. Must be one of these.

 

[E270 Owner]

As previously posted......

New rear battery
New alternator

Both tested and working correctly.

SBC battery not changed but I cant see it causing all those faults



Just looking at a wiring diagram ................. looks like a SAM unit is faulty














.

 

[E270 Owner]

Tip: always check main dealer prices

Customer has advised me that a secondhand rear sam unit can be bought on e-bay for @ £120 + P&P

I told customer a new one from MB is only £139.50 +vat