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Home >> Porsche >> 1992 >> 911 Turbo F6-3299cc 3.3L SOHC Turbo >> Repair and Diagnosis >> Powertrain Management >> Technical Service Bulletins >> All Technical Service Bulletins >> Campaign - Defective Turbo Control Unit Software >> Work Procedure
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Work Procedure


Service Action 291


1. Move left seat forward to stop position and height adjustment front and rear upward to stop position.


2. Remove carpet behind left seat.

Figure 1:





3. Disconnect wiring plug from turbo control unit located under the left seat right side (Part Number 965 618 130 00). (Arrow in Figure 1.)


4. Use a short phillips screwdriver to remove the two turbo control unit mounting screws.


5. Remove control unit.

Note: Model year 1992 vehicles, VIN range: WP0AA296 - NS480240 to WP0AA296 - NS480290 should be checked to determine if the new version turbo control unit has been already installed. If the production date, stamped on the turbo control unit, is October 29, 1991 or later and the control unit is marked with a green dot, the control unit is okay and must be reinstalled.


6. Install new turbo control unit (with above noted exception) and tighten the mounting screws.


7. Connect wiring plug.


8. Install carpet.


9. Adjust left seat to the original position.

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