Shift Interlock Switch: Service and Repair

Transmission Park Selector Switch (F305)

Transmission park selector switch consists of two micro switches. The two micro switches create the signal that the electronic ignition key removal lock needs to release the key only when the selector lever is in P.

The first micro switch is closed when the shift lock solenoid (N110) is not active when the selector lever is in "P" (brake pedal not pressed) and also the selector lever manual release below the ashtray is not actuated.

The second micro switch is closed when the button on the selector lever handle is not actuated in selector lever position "P".

Following points must be observed before replacing the transmission park selector switch:

- Vehicle diagnostic tester connecting.

1. Both micro switches are switched electrically in sequence, that is, both switches must be closed for ignition key to be removed. Check the micro switch in Guided Fault Finding using vehicle diagnostic tester. After the "Vehicle System Test":

- Select the following menu items on vehicle diagnostic tester.

• Go to

• Function/Component Selection

• Drive

• Automatic Transmission 0C8

• 01 - On Board Diagnostic (OBD) Capable Systems

• 02-Transmission Electronics

• Electrical Components

• Test program F305 - Transmission Park Selector Switch

2. An electrical test on the micro switch is also possible. If a continuity test is performed with a multimeter, note that in this case, there is a resistance value of approximately 470 Ohm when both switches are closed.

Removing






- Shifter mechanism function unit, removing. Refer to => [ Shift Mechanism Function Unit ] Shift Mechanism Function Unit.

- Remove the shift gate. Refer to => [ Shift Gate ] Shift Gate.

- Pry out the retaining pin - A - in direction of - arrow - with a screwdriver.

- Remove the first micro switch - B -.

- Disengage electrical wiring from tab - arrow C - and remove micro switch from shift mechanism.

- Disconnect the connector - D - from the shift lock solenoid.






- Disconnect the connector - E - upward.

- Push the tab - C - in direction of - arrow 1 -.

- Remove the second micro switch - B - in direction of - arrow 2 -.

- Disengage electrical line at selector mechanism - arrow A -.

Installing






• Coat the bearings and the sliding surfaces with polycarbamide grease (G 052 142 A2).

- Guide micro switch on longer electrical line into opening under parking lock button in selector mechanism.

- Install the shift gate - 1 - from underneath.

• Shift gate selector lever in "S" (as illustrated).

- Install the micro switch - B - into the shift gate and secure it with the retaining pin - A -.

• The micro switch must be flush on all sides.

- Attach the electric wire to the tab - arrow C -.

• Retaining screws - A - secure the micro switch - B - inside the shift gate.

• The ignition key removal lock will not function correctly if the micro switch is not inserted correctly or properly secured.

- Secure the electric wire - arrows A - to the selector mechanism as illustrated.






- Install the micro switch - B -.

• The ignition key removal lock will not function correctly if the micro switch is not inserted correctly or properly secured.

Install in reverse order of removal. Note the following:

- Install the shift gate. Refer to => [ Shift Gate ] Shift Gate.

- Install shift mechanism function unit. Refer to => [ Shift Mechanism Function Unit ] Shift Mechanism Function Unit.