Looking for insight from techs or anyone familiar with AMG cooling system diagnostics/repairs.

I’m the original and only owner of a 2024 GLE 63 S, and the vehicle has been under full Mercedes warranty since new. No independent shops or third-party service centers have ever touched the vehicle — only authorized Mercedes-Benz dealers.

I recently moved out of state and brought the vehicle to a new dealer for service and an engine light. During inspection they found what they described as a failing non-OEM repair related to the charge air cooler coolant temperature sensor circuit.

What’s interesting is that the exact same fault appears multiple times in the vehicle’s XENTRY history from prior dealer visits. The car has only been to Mercedes dealers. The one I purchased from, the one who maintained it and now the new dealer where we moved.

Fault history:

• 09/05/2025 — P00E100
“The temperature sensor for the coolant of the charge air cooler has a short circuit to positive.”
Stored fault at approximately 726 miles.

• 04/24/2026 — P00E100
Same fault stored again at approximately 15,792 km / 16,592 km.

• 04/24/2026 — P00DF64
“The temperature sensor for the coolant of the charge air cooler has a malfunction. There is an implausible signal.”

• 05/04/2026 — P00E100
Fault now showing current + stored at approximately 17,024 km.

Only after the 5/4 scan did the dealer inspect and find this issue. After the 4/24 scan I wasnt notified of the issue and as far as I know nothing was done to address it. I only saw it after I asked to see the scan.

Current dealer says there is clearly a non-OEM repair present on the sensor/circuit and that repair is now failing.

My questions for anyone familiar with these cars or dealer-side repairs:

- Have you seen temporary repairs or wiring work done on these charge air cooler temp sensor circuits?
- Is there a known issue with harnesses/sensors on the M177 GLE63S platform?
- Would there ever be a reason a dealer would patch/splice instead of replacing components under warranty?
- Does this sound like a common field fix or something unusual?

Mainly trying to understand what likely happened before escalating further with Mercedes.

Thanks in advance.

 

Curious....were you quoted a repair price at the dealership? If not exorbitant, why not just pay for the repair instead of fighting with Mercedes?

 

The hesitation in paying for the repair is that I basically accept responsibility for a non-OEM fix on the car so that any future issue that they can trace back to that part they won’t warranty.

 

It's my understanding that if code Is stored but not current (in the past), It can't be used as diagnosis other than a record of a past event.
If true, the 4/24 test was only a record, and the most recent would be the only time they could drill down into the problem.

I don't understand why they said "a failing non-OEM repair." Can you get a description in writing of why they think someone messed with the car? You'd either get a coherent explanation, or something you could refute.