Code P057, Shorted Transaxle Temperature Sensor Circuit: Action

WARNING: This page is about a different car, the 1995 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

PCM turns on MIL. PCM substitutes engine coolant temperature value for transaxle temperature until engine coolant temperature reaches 221°F (105°C), then transaxle will be set to hot mode operation.

NOTE: Test numbers refer to numbers on diagnostic chart.

If transaxle temperature sensor is shorted, PCM data PD19 should read 298°F (148°C) or greater. If parameter does not show this, then sensor and wiring are okay. Fault is intermittent.
Checks circuit No. 585 for short. If parameter value stays at -18°F(-28°C) or greater with transaxle connector unplugged, check for short in circuit No. 585, PCM terminal 3F12 or transaxle connector terminal "F".
Checks circuits No. 585 for short to ground inside transaxle. If wiring is okay, replace shorted transaxle temperature sensor.

Fig 1: Code P057 Schematic, Shorted Transaxle Temp. Sensor Circuit

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code P057 Diagnostic Flow Chart, Shorted Transaxle Temp. Sensor Circuit

Courtesy of GENERAL MOTORS CORP.