Overdrive Switch: Description and Operation

Location, Drive to 4th Switch

Operation

NOTE: The rotary position switch is NOT adjustable.

The position of the gear selector lever is detected by the range sensor; a system which consists of two sensors (switch systems).
1. The rotary position switch, which is located on the RH side of the transmission case and is coaxial with the selector shaft.
2. The D to 4 (micro) switch, which is mounted in the 'J gate' assembly.

When the selector is moved across the gate to engage 4, or back from that side towards D the selector cable does not move. In order that this change of state be registered by the TCM the D to 4 switch is incorporated.

The rotary switch in isolation provides a 4-bit code, which, when added to the D to 4 switch becomes a 5-bit code. The TCM will make a failure judgement if it detects an 'illegal' code.