DTC Troubleshooting
DTC P0957: Short in Transmission Gear Selection Switch Circuit, or Transmission Gear Selection Switch Stuck ONNOTE:
^ 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. Start the engine in P, and wait for at least 10 seconds.
2. Verify the transmission gear selection switch sequential sportshift mode switch signal inputs with the HDS in the A/T data list.
Is sequential sportshift mode SW ON?
YES - Go to step 3.
NO - Intermittent failure, the system is OK at this time. Check the S-MODE wire for an intermittent short between the transmission gear selection switch and the PCM.
3. Turn the ignition switch to LOCK (0).
4. Disconnect the transmission gear selection switch/park pin switch/A/T gear position indicator panel light connector.
5. Turn the ignition switch to ON (II).
6. Verify the transmission gear selection switch sequential sportshift mode switch signal inputs with the HDS in the A/T data list.
Is sequential sportshift mode SW ON?
YES - Go to step 7.
NO - Replace the transmission gear selection switch, then go to step 18.
7. Turn the ignition switch to LOCK (0).
8. Jump the SCS line with the HDS.
9. Disconnect PCM connector E (31P).
10. Check for continuity between transmission gear selection switch/park pin switch/A/T gear position indicator panel light connector terminal No. 3 and body ground.
Is there continuity?
YES - Repair short in the wire between PCM connector terminal E30 and the transmission gear selection switch, then go to step 18.
NO - Go to step 11.
11. Connect the transmission gear selection switch/park pin switch/A/T gear position indicator panel light connector.
12. Update the A/T software in the PCM if it does not have the latest software, or substitute a known-good PCM.
13. Start the engine in P, wait for at least 10 seconds, then shift to M.
14. Push the shift lever toward the upshift position (+) slowly, and release it; repeat this test at least 10 times.
15. Pull the shift lever toward the downshift position (-) slowly, and release it; repeat this test at least 10 times.
16. Check for DTC(s) in the DTCs/Freeze Data in A/T Mode Menu with the HDS.
Is DTC P0957 indicated?
YES - If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.
NO - Go to step 17.
17. Monitor the OBD STATUS for P0957 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the HDS 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 on step 16, go to the indicated DTC's troubleshooting.
NO - Check for poor connections and loose terminals at the transmission gear selection switch and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, return to step 13 and recheck.
18. Clear the DTC with the HDS.
19. Start the engine in P, wait for at least 10 seconds, then shift to M.
20. Push the shift lever toward the upshift position (+) slowly, and release it; repeat this test at least 10 times.
21. Pull the shift lever toward the downshift position (-) slowly, and release it; repeat this test at least 10 times.
22. Check for DTC(s) in the DTCs/Freeze Data in A/T Mode Menu with the HDS.
Is DTC P0957 indicated?
YES - Check for poor connections and loose terminals at the transmission gear selection switch and the PCM, then go to step 1.
NO - Go to step 23.
23. Monitor the OBD STATUS for P0957 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the HDS indicate PASSED?
YES - Troubleshooting is complete. If any other DTCs were indicated on step 22, go to the indicated DTC's troubleshooting.
NO - Check for poor connections and loose terminals at the transmission gear selection switch and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, return to step 19 and recheck.