Emissions - Check Engine Light ON/DTC's P2036/P203A Set
Date: November 7, 2001Order No.: P-B-07.61/15
Supersedes:
Group: 07
SUBJECT:
Model Year 2001, SLK230 (170.449) and Model Year 2002, C230K (203.747)
Check Engine Light Activated with DTC P2036 (P0410) or P203A / Engine
Performance Complaint
In the above referenced models, should you experience instances of check engine light with code P2036 (P0410) or P203A or engine performance complaints, this may be caused by an air injection system component failure and/or an engine wiring harness problem. Please follow the below steps to remedy this condition.
Note:
With 9/01 DAS update, a test to check the air injection logic chain on Mill with SIM4 injection system has been added.
Remedy:
1. Check all components (shut off valve, check valve, switch over valve, vacuum lines and connections) of the air injection system for proper function and correct routing.
2. A bad contact in the wiring harness from the engine ECU to flap M 16/7 at splice Z 7/27 which is located either in the harness tray on the left side of the engine, or between the fire wall and the harness tray may be influencing the correct function of the flap.
3. Measure the resistance in the 5V supply voltage line in the engine wiring harness from the Engine ECU (pin 30) to the recirculating air flap (M 16/7 - pin 3) with an Ohmmeter.
4. If the resistance increases by more than 0.5 ohms while moving the wiring harness (turn-twist pull-push), check the position of the splice connection Z 7/27.
5. If connection Z 7/27 of the engine wiring harness is found to be in the harness tray on the left side (drive direction) at the engine, remove the sleeve's insulation, re-solder and insulate it using a new heat shrink wrap.
6. If connection Z 7/27 of the engine wiring harness is found to be between the fire wall and the harness tray (not in the harness tray), the engine wiring harness needs to be replaced.
Note:
Wiring harness with a production date of CW31 (week of 7/30/01) or later are of an updated configuration.