Affected Component: ELECTRICAL SYSTEM

Date Published
DEC 01, 2023
NHTSA TSB #
10248212
TSB Document
Summary
In our continuing efforts to assure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA, LLC ("MBUSA") is extending the warranty coverage on the engine thermostat (including software update) installed in certain Model Year ("MY") vehicles (with engines M176, M177, M178) listed below from the original New Vehicle Limited Warranty of 4 years/50,000 miles to 15 years/150,000 miles (whichever occurs first), due to the following condition: In the affected vehicles, the sealing ring in the engine thermostat could detach, causing a delay in the heating of the engine coolant. This may also cause the check engine Malfunction Indicator Lamp ("MIL") to illuminate. Please follow the work instructions added to this NCU to remedy the issue. Please be advised that all repairs being claimed under this extended warranty must have a quick test uploaded with the following fault code information and may be audited. P012800 - Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature) All repairs found to be functioning properly or without proper documentation will be returned and the claim debited in full. Only the following damage codes and parts may be claimed for the aforementioned repairs: Damage Code(s): 20102 - Insert, coolant thermostat o 52 - Does not operate correctly o 41 - Hard closing 20103 - Housing/cover, coolant thermostat o 73 - Electrical fault 2030T - Heating element, coolant thermostat o 53 - Insufficient effect/power o 73 - Electrical fault