Daimler AG (“DAG”), the manufacturer of Mercedes-Benz vehicles, has determined that on the various Model...

Bulletin number

EW- ECU Software

Component

Engine

Summary

Daimler AG (“DAG”), the manufacturer of Mercedes-Benz vehicles, has determined that on the various Model Year (“MY”) 2014 - 2018 Mercedes-Benz vehicles listed below, the engine control unit (ECU) software may not meet current specifications. In certain circumstances when the vehicles are parked for a long duration, an erroneous activation of the “Check Engine Lamp” for the outside temperature sensor might occur. In our continuing efforts to assure the proper performance of Mercedes-Benz products and to ensure the satisfaction of our customers, the warranty for the ECU software in the subject vehicles has been extended from the original 4 years/50,000 miles to 10 years/120,000 miles. This ECU software extended warranty is applicable to the following vehicles: In the event of an illuminated ”Check Engine Lamp” which leads to a diagnosis of a fault with the outside temperature sensor, the following fault codes may be present: Motor Electronics (ME) N3/10 P007128 (for M274/276LA engine) – Ambient Air Temperature Sensor Circuit “A’ Range/Performance signal bias level out of range/zero adjustment failure or ME N3/10 P007028 (for M270 engine) – Ambient Air Temperature Sensor Circuit “A’ signal bias level out of range/zero adjustment failure In this event, guided tests will be available in Xentry which will lead to the update of the engine control unit software. The following damage codes may be used: 54 575 90 Update Engine Control Unit Software. Please check the VIN in Netstar/VMI before scheduling the appointment for the repair. Applicable vehicles will display an extended warranty service package in Netstar/VMI on March 12, 2019. After the distribution of this NCU, a letter will be sent to owners of certain vehicles informing them that the warranty for the ECU software for fault codes related to the Outside Temperature Sensor will be extended from the original 4 years/50,000 miles to a total of 10 years or 120,000 miles (whichever occurs first). If customers have already paid to have the outside temperature sensor replaced, they may be eligible for reimbursement. Please advise the customer to follow the instructions detailed below (also included in a copy of the customer letter).

Owners of these vehicles have filed 680 complaints in the engine category.