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Home >> Audi >> 2021 >> S6 Prestige >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> On Board Diagnostic (HVAC) >> 01 On Board Diagnostic >> Diagnosis And Testing >> Function 07, Code Control Module >> A/C control head coding
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A/C control head coding

1st and 2nd digits (where applicable)
Code Description
00 _ _ _ not used
3rd digit
Code A/C compressor type
0 _ _ Zexel
1 _ _ Nippondenso
4th digit
Code Engine application
_ 5 _ 5-cylinder
_ 6 _ 6-cylinder
5th digit
Code Market version Engine type
_ _ 2 USA/Canada Gasoline
NOTE:

Zexel A/C compressors have been installed from the start of production. During m.y. : 1996  , a new Nippondenso A/C compressor is installed as a running change on all vehicles with 6-cylinder engines.

On the Nippondenso compressor, A/C compressor speed sensor -G111- - has been eliminated. The compressor is instead protected by an overheat fuse in A/C clutch -N25-.

The A/C control headA/C control head -E87- must be coded for the specific vehicle application, including the type of A/C compressor installed (Zexel or Nippondenso).

Vehicles equipped with a Nippondenso compressor must have an A/C control headA/C control head -E87- identified with index letter "K" or higher to allow for correct coding.

For correct part number and application of replacement A/C control headA/C control head -E87- Refer to latest parts information.

The software version displayed with A/C control head identification (shown here as "DXX") has no significance for Service Department use.

Indicated on display

Rapid data transfer HELP 
Select function XX 

-- Press buttons and to select "Code Control Module" function 07.

Indicated on display

Rapid data transfer Q 
07 - Code Control Module 

-- Press button to confirm input.

Indicated on display

Code control module 
Enter code number XXXXX (0-00127) 

-- Using keypad on Scan Tool: VAG1551  , enter code for A/C control head according to compressor type, engine cylinder configuration and market version A/C control head coding .

Examples:

Coding Market version Compressor Engine
00062 USA/Canada Zexel 6-cyl. gasoline
00162 USA/Canada Nippondenso 6-cyl. gasoline

-- Press button to confirm input.

A/C control head identification and coding are displayed

4A0 820 043 A Klima-Vollautomat DXX → 
Coding 00062 WSC 23890 

-- Press →  button.

NOTE:

Vehicles equipped with a Nippondenso compressor must have an A/C control headA/C control head -E87- identified with index letter "K" or higher to allow for correct coding.

For correct part number and application of replacement A/C control headA/C control head -E87-

Indicated on display

Rapid data transfer HELP 
Select function XX 

-- Carry out basic setting FUNCTION 04, BASIC SETTING VAG 1551 .

-- Check DTC memory DIAGNOSTIC TROUBLE CODE MEMORY, CHECKING AND ERASING .