Mercedes R Klasse Diesel Fuel Filter Heater Issue

Evening. My 2010 Mercedes R Klasse, diesel engine, is showing some errors. I'm getting an error related to the fuel filter heater circuit. I've also noticed a power loss, poor engine response, increased fuel consumption, and the engine is idling unevenly. I suspect it may be a defective cable or plug connection to the heater itself. Has anyone else experienced something similar with their diesel engine setup? Filter replacement was done recently, but the issue persists. Engine stalling hasn't occurred yet but the rough idle is concerning.

A faulty fuel filter heater can cause those symptoms, especially the power loss and rough idle in a diesel engine. Given the error code points to a wiring issue, I would suggest inspecting the connector and wiring harness leading to the fuel filter heater. Check for any signs of corrosion, damage, or loose connections. Has the fuel consumption increased gradually, or did it happen suddenly?

Thanks. The fuel consumption seemed to jump up fairly quickly, coinciding with the other symptoms. I'll inspect the wiring more closely. When you say 'wiring harness', are you referring to the entire loom or just the immediate connector to the fuel filter itself?

When I mention the wiring harness, I mean the section of wires and connectors directly associated with the fuel filter and its heater. Given the sudden increase in fuel consumption, it's plausible the heater is drawing excessive current due to a short, or not functioning at all, causing the engine management system to compensate. If you are not comfortable with electrical diagnostics, it might be prudent to have a workshop investigate before further issues arise. Appreciate the advice. I checked the wiring as best I could, and nothing obvious jumped out. I took it to a local independent garage. It was indeed a corroded connector to the fuel filter heater, just as you suspected, causing all the issues. Repair cost was 95€. At least it's sorted, thanks again for your input.