Transmission Control Systems

TROUBLE CODE 31
THROTTLE POSITION SENSOR

Diagnosis
Input signal circuit of Throttle Position Sensor is open or shorted.

Trouble Symptom
Shift point too high or too low; Engine brake not effected in "3" range; excessive shift shock; excessive tight corner "braking".












1. Check harness connector between Transmission Control Module (TCM) and Throttle Position Sensor.
a. Turn Ignition Switch to "OFF".
b. Disconnect connector from TCM and Throttle Position Sensor.






c. Measure resistance of harness connector between TCM and Throttle Position Sensor.
Connector & Terminal / Specified Resistance:
(B54) No. 8 - (E13) No. 2 / 1 Ohm, or less.
(B56) No. 19 - (E13) No. 3 / 1 Ohm, or less.






d. Measure resistance of harness connector between TCM and body to make sure that circuit does not short.
Connector & Terminal / Specified Resistance:
(B54) No. 8 - Body / 1 M-Ohms or more.
(B56) No. 19 - Body / 1 M-Ohms, or more.

2. Check Throttle Position Sensor.






Measure resistance between Throttle Position Sensor terminals.
Terminals / Specified Resistance:
(E13) No. 1 - No. 2
0.3 - 0.7 k-Ohms, (Throttle fully closed.)
3 - 6 k-Ohms, (Throttle fully open.)
(E13 No. 1 - No. 3 / 3.5 - 6.5 k-Ohms.

3. Check input signal for TCM.
a. Connect connectors to TCM and Throttle Position Sensor.
b. Turn Ignition Switch "ON" (with Engine "OFF").






c. Measure signal voltage input emitted from Throttle Position Sensor with Accelerator Pedal fully depressed.
Connector & Terminal / Specified Voltage:
(B54) No. 8 - No. 7
0.5 ± 0.2 Volts (Throttle fully closed.)
4.6 ± 0.2 Volts (Throttle fully open.)

Using Subaru Select Monitor






1. Connect connectors to TCM and Throttle Position Sensor.
2. Turn Ignition Switch to "OFF".
3. Connect the Subaru Select Monitor to Data Link Connector.
4. Turn Ignition Switch to "ON" and Subaru Select Monitor switch to "ON".
5. Designate mode using function key.
6. Read data on Subaru Select Monitor.
Function mode: F09

Specified Data:
0.5 ± 0.2 Volts (Throttle fully closed.)
4.6 ± 0.2 Volts (Throttle fully open.)
(Must be changed correspondingly with Accelerator Pedal operation (from "released" to "depressed" position).

4. Check Power supply to Throttle Position Sensor.
a. Turn Ignition Switch to "OFF".
b. Disconnect connector from Throttle Position Sensor.
c. Turn Ignition Switch to "ON".






d. Measure power supply voltage to Throttle Position Sensor.
Connector & Terminal / Specified Voltage:
(E13) No. 1 - Body / 5.12 ± 0.1 Volts.

Using Subaru Select Monitor






1. Turn Ignition Switch to "OFF".
2. Connect the Subaru Select Monitor to Data Link Connector.
3. Turn Ignition Switch to "ON" and Subaru Select Monitor switch to "ON".
4. Designate mode using function key.
5. Read data on Subaru Select Monitor.
Function mode: F14

Specified Data:
5.12 ±0.1 V