Tech Tip: Mercedes-Benz MIL On/DTC P2034 Stored in ECU – UnderhoodService

Tech Tip: Mercedes-Benz MIL On/DTC P2034 Stored in ECU

If you receive customer reports in the affected model vehicles of the "check engine" light being activated after starting the engine, and code P2034 is stored in the engine control unit, the cause may be that the

If you receive customer reports in the affected model vehicles of the “check engine” light being activated after starting the engine, and code P2034 is stored in the engine control unit, the cause may be that the ­engine ECU has detected a faulty crankshaft sensor during start up of the engine due to the camshaft ­sensor.

Affected Vehicles:

• Model 163.154/157/172/175;
• Model 164.175; and
• Model 463.249.

Note: Only vehicles with production date prior to July 2005 are affected.

This condition can be verified by checking the following values in the freeze-frame data:

Vehicle speed: 0
Engine speed: 0
Time since engine start: 0

If confirmed by freeze-frame data values, proceed as follows to resolve.

Service Procedure:

1. Check to confirm that the camshaft sensor P/N A004 153 96 28 is installed.

2. If P/N A004 153 96 28 is installed, perform the engine control unit software flash with 11/05 DAS or later.

Note: After the software flash, perform SCN coding. Refer to Star Tek Info Document S-B-07.61/38g or
S-B-58.00/144a dated Feb. 4, 2006, for the procedure.

Note: Do not replace the crankshaft sensor and camshaft sensor.

Courtesy of Mitchell 1.

For more information on Mitchell 1 products and services, automotive professionals can visit the company’s website at www.mitchell1.com.

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