P0731

DTC P0731: Problem in 1st Clutch and 1st Clutch Hydraulic Circuit (1st gear incorrect ratio)

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review General Troubleshooting Information.

1. Warm up the engine to normal operating temperature (the radiator fan comes on).
2. Make sure that the transmission is filled to the proper level, and check for fluid leaks.
3. Drain the ATF through a strainer. Inspect the strainer for metal debris or excessive clutch material.

Does the strainer have metal debris or excessive clutch material?

YES - Replace the transmission, then go to step 13.

NO - Replace the ATF, then go to step 4.

4. Measure the line pressure.

Is the line pressure within service limit?

YES - Go to step 5.

NO - Repair the ATF pump and the regulator valve, or replace the transmission, then go to step 13.

5. Measure the 1st clutch pressure.

Is the 1st clutch pressure within service limits?

YES - Go to step 6.

NO - Shift valves B and C are stuck. Repair these valves and the hydraulic circuit, or replace the transmission, then go to step 13.

6. Test stall speed with the shift lever in 1.

Is the stall speed within service limits?

YES - Go to step 7.

NO - Shift valves A and D are stuck. Repair these valves and the hydraulic circuit, or replace the transmission, then go to step 13.

7. Turn the ignition switch to ON (II).
8. Clear the DTC with the HDS.
9. Test-drive the vehicle in 1st gear with the shift lever in D at speeds over 7 mph (12 km/h) and the engine speed above 1,000 rpm, for at least 12 seconds.
10. Turn the ignition switch to LOCK (0). Repeat the test-drive in step 9, then go to step 11.
11. Check for DTCs with the HDS.

Is DTC P0731 indicated?

YES - Repair the 1st clutch, or replace the transmission, then go to step 13.

NO - Go to step 12.

12. Monitor the OBD STATUS for P0731 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED?

YES - Troubleshooting is complete. If any other DTCs were indicated in step 11, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, repair the 1st clutch, or replace the transmission. If the HDS indicates NOT COMPLETED, go to step 9.

13. Test-drive the vehicle in 1st gear with the shift lever in D at speeds over 7 mph (12 km/h) and the engine speed above 1,000 rpm, for at least 12 seconds.
14. Turn the ignition switch to LOCK (0). Repeat the test-drive in step 13, then go to step 15.
15. Check for DTCs with the HDS.

Is DTC P0731 indicated?

YES - Check for poor connections or loose terminals at the input shaft (mainshaft) speed sensor and the output shaft (countershaft) speed sensor and the PCM, then go to step 4.

NO - Go to step 16.

16. Monitor the OBD STATUS for P0731 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED?

YES - Troubleshooting is complete. If any other DTCs were indicated in step 15, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, check for poor connections or loose terminals at the input shaft (mainshaft) speed sensor and the output shaft (countershaft) speed sensor and the PCM, then go to step 4.
If the HDS indicates NOT COMPLETED, go to step 13.