DTC Troubleshooting
DTC P0721: Problem in Output Shaft(Countershaft) Speed Sensor CircuitDTC P0722: Problem in Output Shaft(Countershaft) Speed Sensor Circuit (No Signal Input)
NOTE:
^ Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.
^ 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 ON (II).
2. Clear the DTC with the HDS.
3. Raise the front of the vehicle, make sure it is securely supported, and allow the front wheels to rotate freely. Or raise the vehicle on a lift.
4. Check for proper output shaft (countershaft) speed sensor installation.
5. Start the engine, disable the VSA by pressing the VSA OFF switch, run the vehicle in the D position with engine speed 2,000 rpm or higher for more than 10 seconds. Slowdown and stop the wheels.
6. Monitor the OBD STATUS for P0721 or P0722 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES - Go to step 7.
NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals between the output shaft (countershaft) speed sensor and the PCM. If the screen indicates NOT COMPLETED, go to step 5.
7. Turn the ignition switch OFF.
8. Jump the SCS line with the HDS.
9. Disconnect PCM connectors A (31P) and B (24P), and the output shaft (countershaft) speed sensor connector.
10. Check for continuity between PCM connector terminal A3 and body ground, and between PCM connector terminal B15 and body ground.
Is there continuity?
YES - Go to step 11.
NO - Repair open in the wires between PCM connector terminals A3, B15, and ground (G101), or repair poor ground (G101), then go to step 30.
11. Connect PCM connectors A (31P) and B (24P).
12. Turn the ignition switch ON (II).
13. Measure the voltage between output shaft (countershaft) speed sensor connector terminal No. 1 and body ground.
Is thereabout 5 V?
YES - Go to step 14.
NO - Go to step 25.
14. Turn the ignition switch OFF.
15. Disconnect PCM connector B (24P).
16. Check for continuity between output shaft (countershaft) speed sensor connector terminal No. 2 and body ground.
Is there continuity?
YES - Repair short to body ground in the wire between PCM connector terminal B19 and the output shaft (countershaft) speed sensor, then go to step 30.
NO - Go to step 17.
17. Check for continuity between output shaft (countershaft) speed sensor connector terminal No. 3 and PCM connector terminal C4.
Is there continuity?
YES - Go to step 18.
NO - Repair open in the wire between the output shaft (countershaft) speed sensor connector and PCM connector terminal C4, then go to step 30.
18. Connect PCM connector B (24P).
19. Turn the ignition switch ON (II).
20. Measure the voltage between output shaft (countershaft) speed sensor connector terminals No. 2 and No. 3.
Is there about 5 V?
YES - Go to step 21.
NO - Go to step 29.
21. Connect the output shaft (countershaft) speed sensor connector.
22. Measure the voltage between PCM connector terminals B19 and A3.
Is the voltage 0 V or about 5 V?
YES - Go to step 23.
NO - Replace the output shaft (countershaft) speed sensor, then go to step 30.
23. Shift to the P position. Start the engine, and let it idle.
24. Shift to the D position, and measure the voltage between PCM connector terminals B19 and A3.
Is there 1.5-3.5 V?
YES -Go to step 36.
NO - Replace the output shaft (countershaft) speed sensor, then go to step 30.
25. Measure the voltage between PCM connector terminals C6 and A3.
Is there about 5 V?
YES - Repair open in the wire between PCM connector terminal C6 and the output shaft (countershaft) speed sensor, then go to step 30.
NO - Go to step 26.
26. Turn the ignition switch OFF.
27. Disconnect PCM connector C (22P).
28. Check for continuity between PCM connector terminal C6 and body ground.
Is there continuity?
YES - Repair short to body ground in the wire between PCM connector terminal C6 and the output shaft (countershaft) speed sensor, then go to step 30.
NO - Go to step 36.
29. Measure the voltage between PCM connector terminals B19 and A3.
Is thereabout 5 V?
YES - Repair open in the wire between PCM connector terminal B19 and the output shaft (countershaft) speed sensor, then go to step 30.
NO - Go to step 36.
30. Reconnect all connectors.
31. Turn the ignition switch ON (II).
32. Clear the DTC with the HDS.
33. Start the engine, disable the VSA by pressing the VSA OFF switch, run the vehicle in the D position with engine speed 2,000 rpm or higher for more than 10 seconds. Slow down and stop the wheels.
34. Check for DTCs with the HDS.
Is DTC P0721 or P0722 indicated?
YES - Check for poor connections or loose terminals between the output shaft (countershaft) speed sensor and the PCM, then go to step 1.
NO - Go to step 35.
35. Monitor the OBD STATUS for P0721 or P0722 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete. If any other DTCs were indicated in step 34, go to the indicated DTC's troubleshooting.
NO - If the screen indicates FAILED, check for poor connections or loose terminals between the output shaft (countershaft) speed sensor and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 33.
36. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
37. Start the engine, disable the VSA by pressing the VSA OFF switch, run the vehicle in the D position with engine speed 2,000 rpm or higher for more than 10 seconds. Slow down and stop the wheels.
38. Check for DTCs with the HDS.
Is DTC P0721 or P0722 indicated?
YES - Check for poor connections or loose terminals between the output shaft (countershaft) speed sensor and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 37. If the PCM was substituted, go to step 1.
NO - Go to step 391.
39. Monitor the OBD STATUS for P0721 or P0722 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. If any other DTCs were indicated in step 38, go to the indicated DTC's troubleshooting.
NO - If the screen indicates FAILED, check for poor connections or loose terminals between the output shaft (countershaft) speed sensor and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 37. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 37.