Technical Service Bulletin Inside Door Latch Mechanism

Subject:   Inside Door Latch Mechanism                 Models: 911 1985

Bulletin Number: 86 – 05

To reduce the operating force on the inside door latch, the mechanism has been modified.

  1. Cable is replaced by Bowden cable with spring.
  2. Reversing bracket with more favorable reversing ratio.
  3. Pull rod length changed.

Instruction:                                 March 20, 1985

As of VIN:                                    91 7FS 121.227

                                                        91 9FS 161.176

                                                        91 9FS 170.577

New Part Numbers:

  1. 911.531.509.01 Cable
  2. 911.531.083.01 Bracket Left
  3. 911.531.084.01 Bracket Right
  4. 911.531.091.01 Pull Rod
  5. 999.507.009.02 Snap Nut 3.5mm
  6. 900.145.032.02 Metal Screw 3.5 x 13mm

The modified inside door mechanism can be installed retroactively as of M.Y 1974.

door mechan

Work procedures:

  1. Remove door trim panel (window remains closed). (Special Tool P9231 is needed)
  2. Pull off plastic foil.
  3. Remove reversing bracket with spring and pull rod.
  4. Remove bracket (A) and unclip cable on door lock. Remove cable (note routing)
  5. Pull off both snap nuts. Mark location of holes (see sketch). Center punch and drill holes 5+0.2mm. (Some 85 model cars already have these holes)
  6. Treat edges of holes with rust preventing paint.
  7. Connect new cable on door lock and bracket (3).
  8. Mount cable with bracket (A).
  9. Install new reversing bracket with new pull rod. IMPORTANT: Pull rod on long lever arm, cable on short lever arm.
  10. Paste on plastic foil and reinstall door trim panel.

Conversion time:

One Door 140 T.U.

Both Doors 270 T.U.

door chart

Hole Pattern (Seen from below) / Scale: 1:1 (mm)

door chart 1

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