Mercedes Benz SLK R172 - Engine Warning Light On | HELLA

Mercedes Benz

SLK R172

Model Year: 2011 – 2016

Engine: OM651

Engine Warning Light On

Error Code: P04091C, P040496, P040600

Faulty Position Sensor for Electric Exhaust Gas Recirculation Actuator…..

If the fault described above occurs together with the listed error codes, a possible cause is a faulty EGR valve (exhaust gas recirculation valve).


In order to exclude other sources of the problem, first check the periphery (power supply, plug connections, etc.) of the exhaust gas recirculation system.

If no fault is determined here, check the article number of the EGR valve.

The items with the following article numbers are faulty

- A651 140 06 60

- A651 140 07 60

These parts must be replaced with an updated EGR valve with the article number A651 140 08 60.

After the EGR valve has been replaced, read the error memory of the vehicle using a diagnostic unit and delete existing error codes.

A test drive should then be carried out and the error memory read again.

Important safety note Technical information and practical tips have been compiled by HELLA in order to provide professional support to vehicle workshops in their day-to-day work. The information provided on this website is intended for use by suitably qualified personnel only. Reprinting, distribution, reproduction, exploitation in any form or disclosure of the contents of this document, even in part, is prohibited without our express, written approval and indication of the source. The schematic illustrations, pictures and descriptions serve only for the purposes of explanation and representation of the instructions and cannot be used as a basis for installation or assembly work. All rights reserved.