Instrument cluster modification (Strange wire added)

[Sun]

Hi everyone,

We are having some problems with our 2004 Sprinter (Dodge 2500). While trying to search for the cause of the problem, we discovered a cable soldered on to the back of our instrument cluster. The pictures show the cluster with the small green wire soldered close to where the power connection and the three capacitors are located (right hand side). The red arrows should show the two points where the wire has been soldered on.

Could anyone tell us what this is for?
Is it maybe some sort of immobilizer workaround?

All ideas warmly welcomed,
Sun

 

[GeorgeRa]

Whoever wired these points had an engineering knowledge of the PC diagram. I would think it is an internal factory response to an R&D’s oopsie. I don’t think it is MB guided fix by a dealer, it takes some skills to solder into a heavily populated surface mounted board without damaging it.

George.

 

[MercedesGenIn]

Hi there,
This is the power supply section to the cluster, it looks to me like one of the pins from the white multi-way cluster connector has been grounded. Factory modification as GeorgeRa points out. Probably an input or output that is unused and is strapped to ground to prevent it 'floating' voltage-wise for interference suppression purposes.
All the best
Steve

 

[ECU]

How about remote starting? For the remote start, you need a feed for when the glow plugs are done heating. Could it be that?

 

[Sun]

Thanks for the super quick responses everyone.

In a way I was hoping it might be a bit more unusual, because that could help explain our issues. We originally started inspecting the cluster because just before the trouble began I heard a quiet sound emanating from the dash area. It sounded like a small dry leaf rattling around in an air duct or possibly like a crisp/chips packet being crinkled (definitely no leaves in the air duct or crisp packets).

Does anyone know if that sort of noise could originate in the cluster area? Could it be a flaky capacitor or something? I was hoping to find some kind of short in this area and the wires at the back of the cluster look perfect.