DTC 29

CODE NO.29: VEHICLE SPEED SENSOR SYSTEM












CIRCUIT OPERATION
- A 5 volt voltage is applied to the vehicle speed sensor output terminal (terminal 3) from the PCM (terminal 80). The vehicle speed sensor generates a pulse signal when the output terminal is opened and ground.
- The PCM compares the vehicle speed sensor signal to input shaft and output shaft speed sensor signals.
- If the vehicle speed sensor becomes inoperative, the transaxle will not shift normally.

DTC SET CONDITIONS
If the PCM detects no pulse signal from the vehicle speed sensor for continuous period of thirty seconds under following conditions, it is judged as a vehicle sensor system malfunction and DTC number "29" is displayed.
- Driving forward
- Output shaft speed is 900 r/min or more

TROUBLESHOOTING HINTS
The most likely causes for this case:
- Malfunction of the vehicle speed sensor circuit
- Damaged harness, connector
- Malfunction of the PCM

DIAGNOSIS

STEP 1. Check The Vehicle Speed Sensor.
Does the speedometer work?
If the speedometer is operating properly, go to Step 2.
If the speedometer is not operating properly, refer to Combination Meter.

STEP 2. Check The Combination Meter Circuit.
1. Disconnect harness connector C-41 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.





3. Measure the voltage between terminal 80 and ground.
- Voltage should be approximately 8 - 12 volts.
If not 8 - 12 volts, repair the connectors or the harness wires between the PCM and the combination meter.
If 8 - 12 volts, go to Step 3.

STEP 3. Check The Harness Connector C-41 At The PCM For Damage.





If harness connector C-41 is damaged, repair or replace it. Refer to Diagnostic Strategies; General Electrical Troubleshooting. Recheck for DTCs.
If harness connector C-41 is in good condition, replace the PCM. On 2000 models, the immobilizer-ECU should be replaced together with it. Refer to Ignition Switch and Immobilizer System.