Transaxle Range Switch

Fig 1: Identifying Automatic Transmission Cable & Selector Lever

Courtesy of GENERAL MOTORS CORP.

The transaxle range switch is located on top of the transaxle. The transaxle range switch contains multiple switches, four of which are used to create a coded signal to the PCM/TCM indicating gear selection. The coded signal can be viewed on the Scan tool as TR Switch - P/A/B/C and gear position indicated can be viewed as transaxle Range. The different combinations of the four PCM/TCM inputs, P/A/B/C, represent selections from Park to 1st or Invalid/Grounded/Open. Refer to table below.

On a vehicle equipped with a 2.2L, switches are all attached to ground on one side. When the switch closes, the PCM input is pulled low (ON). When switch is open input reads high (OFF). On vehicles equipped with a 3.0L, all switches are connected to ignition voltage on one side. When the switch closes, the TCM input is pulled high (ON). When switch is open the input reads low (OFF).