DTC Troubleshooting

DTC Troubleshooting: P0720

DTC P0720: Output Shaft (Countershaft) Speed Sensor Circuit Malfunction

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Initial Inspection and Diagnostic Overview

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

2. Check for Temporary DTCs or DTCs in the A/T SYSTEM with the HDS.

Is DTC P0722 indicated?
YES - Troubleshoot for DTC P0722 in the A/T system. P0721

NO - Go to step 3.


3. Update the PCM if it does not have the latest software, ECM/PCM Update (A/T) or substitute a known-good PCM. Initial Inspection and Diagnostic Overview

4. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 176 °F (80 °C)

- Transmission in D

- ENGINE SPEED between 2,000-4,500 rpm

- Drive for several minutes, then decelerate (with the throttle fully closed) for 5 seconds or more

5. Check for Temporary DTCs or DTCs in the PGM-FI SYSTEM with the HDS.

Is DTC P0720 indicated?
YES - Go to step 6.

NO - Go to step 7.


6. Check for Temporary DTCs or DTCs in the A/T SYSTEM with the HDS.

Is DTC P0722 indicated?
YES - Troubleshoot for DTC P0722 in the AT system. P0721

NO - If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then go to step 4. If the PCM was substituted, check for poor connections or loose terminals at the output shaft (countershaft) speed sensor and the PCM, then go to step 1.


7. Monitor the OBD STATUS for DTC P0720 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the output shaft (countershaft) speed sensor and the PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then go to step 4. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 4.