DTC Troubleshooting

DTC Troubleshooting: P0716, P0721

DTC P0716: Problem in Input Shaft (Mainshaft) Speed Sensor Circuit

DTC P0721: Problem in Output Shaft (Countershaft) Speed Sensor Circuit

NOTE: This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

1. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Raise the vehicle on a lift, make sure it is securely supported, and allow the all four wheels to rotate freely.

4. Start the engine, disable the VSA by pressing the VSA OFF button, run the vehicle with the shift lever in D, and at speeds over 12 mph (20 km/h) for at least 10 seconds. Slow down, and stop the wheels.

5. Check for pending or Confirmed DTCs with the HDS.

Is DTC P0718 or P0723 indicate?
YES - Go to the DTC P0718 troubleshooting P0717 or the DTC P0723 troubleshooting. P0722

NO - Go to step 6.


6. Check for pending or Confirmed DTCs with the HDS.

Is DTC P0716 or P0721 indicated?
YES - Go to step 7.

NO - Intermittent failure, the system is OK at this time.


7. Check the input shaft (mainshaft) speed sensor or the output shaft (countershaft) speed sensor for poor connection and proper installation.

Are there connections and installation OK?
YES - Replace the input shaft (mainshaft) speed sensor or the output shaft (countershaft) speed sensor, then go to step 8.

NO - Connect the speed sensor connector and reinstall the speed sensor, then go to step 8.


8. Turn the ignition switch to ON (II).

9. Clear the DTC with HDS.

10. Start the engine, disable the VSA by pressing the VSA OFF button, run the vehicle with the shift lever in D,and at speeds over 12 mph (20 km/h) for at least 10 seconds. Slow down, and stop the wheels.

11. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0716 or P0721 indicated?
YES - Go to step 1.

NO - Troubleshooting is complete.