I will post the bulletin below on this:
No cooling output, fault code 9006 in air conditioning control unit
Topic number LI83.30-P-049644
Design group 83.30 Air conditioning
Validity All veh. of model series 164/251
Reason for change Remedy and parts availability adapted
No cooling output, fault code (FC) 9006 stored in air conditioning (AAC) control unit.
- Poor system ground at ground point W29/2
- Faulty software in AAC control unit
- Poor ground at refrigerant compressor
1. Check ground point W29/2 (A-pillar, see WIS documents in attachment for details) and repair if necessary.
-> Optimize contact, tightening torque: 9 Nm.
2. Check crimping of ground line of AAC control unit at ground point W29/2 and repair if necessary.
In vehicles produced prior to 04/2010:
3. Flash AAC control unit with flashware (FW)(###) ###-####using Star Diagnosis.
Then perform the following test on the vehicle:
4. Perform the Star Diagnosis tests stored after fault code 9006, including the test of the refrigerant compressor.
5. Check ground line between AAC control unit and ground point W29/2 for open circuit and repair if necessary.
6. Check positive line between AAC control unit and refrigerant compressor for open circuit and repair if necessary.
In vehicles up to code 808 (YoM 07/1) :
7. From the connection of the regulation valve on the refrigerant compressor one cable with a cable lug is bolted onto the housing of the refrigerant compressor as a ground line; the other cable goes via the connector to the engine wiring harness. An additional ground line with a cross section of 0.75 sq.mm must be properly routed from the bolt-on point of the ground cable on the housing of the refrigerant compressor to ground point W16/4 in the front right of the engine compartment below the engine hood hinge (see photos in attachment).
In vehicles as of code 808 (YoM 07/1) :
8. Convert electrical line on refrigerant compressor from 1-pin to 2-pin. (Part number of 2-pin wiring harness A1644406641) When connecting the 2-pin wiring harness, ensure correct polarity otherwise the regulation valve will be irreparably damaged. The regulation valve is thus grounded via the operating unit.
Replacing the refrigerant compressor and the A/C operating unit does not remedy the problem in this case.
Even if the dealer installed a wiring harness this needs to be gone through to see if any issues are found.If this is done and found o.k. let me know.
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