P057

Code Chart P057:

Transaxle Circuit:

CIRCUIT DESCRIPTION
The transaxle temperature sensor is a thermistor, or variable resistor, whose resistance varies based on its temperature. As the temperature of the sensor increases, the resistance decreases. A high transaxle temperature will result in a low signal voltage on CKT 585. Code PO57 sets when the Powertrain Control Module (PCM) sees a transaxle temperature sensor reading of 264°C or greater (0.08 volt or less).

TEST CONDITIONS
1. Test continuously.

FAILURE CONDITIONS
Transaxle temperature sensor valve is 264°C or greater for 5 seconds.

ACTION TAKEN
1. PCM turns "ON" the "Service Vehicle Soon" message.

2. PCM will substitute engine coolant temperature value for transaxle temperature until engine coolant temperature reaches 105°C, then transaxle will be set to hot mode operation.

NOTES ON FAULT TREE
1. If the transaxle temperature sensor is shorted, PCM data PD19 should read 264°C or more. If the parameter does not show this, then the sensor and wiring are OK, and the fault must be intermittent.

2. Checking for CKT 585 shorted. If the parameter value stays at 264°C or greater with the transaxle connector unplugged, the short is in CKT 585, the PCM terminal "3F12," and the transaxle connector pin "F."

3. Checking for a short to ground on CKT 585 inside the transaxle. If wire OK, replace the shorted transaxle temperature sensor.