Mercedes-Benz W164 and W251 Models Fault Code 9006?

[Anthony]

Fault Symptom: The air conditioning does not cool, and the air conditioning control unit (KLA-SG) stores fault code 9006, which means "component A9 (AC compressor) has short circuit" (AC compressor short circuit). Fault Cause: Poor connection of the AC compressor grounding point (W29/2) or software fault in the air conditioning control unit (KLA-SG). Solution: Tighten the AC compressor grounding point (W29/2) with a torque of 9N·m; upgrade the air conditioning control unit (KLA-SG); if necessary, further inspect the power supply and grounding lines of the AC compressor.