DTC Troubleshooting: P0979 (22-3)

DTC P0979:  Short in Shift Solenoid Valve C Circuit

KE, KG, and KS Models


NOTE:

1.Clear the DTC with the HDS.

2.Start the engine, and shift to the D position.

3.Check that DTC P0979 recurs.

Is DTC P0979 indicated?


YES - Go to 7.


NO - Go to 4.


4.Choose Shift Solenoid C in Miscellaneous Test Menu, and test the shift solenoid valve C with the HDS.

5.Start the engine, and shift to the D position.

6.Check the OBD status in DTC Monitor Tool from DTCs/Freeze Data in A/T Mode Menu for a pass/fail test of code P0979.

Did the result indicate a fail?


YES - Go to 7.


NO - Intermittent failure, the system is OK at this time. Check the GRN wire for an intermittent short to ground between the shift solenoid valve C and PCM. If the tester indicates NOT COMPLETE, return to 4 and recheck.n


7.Turn the ignition switch OFF.

8.Jump the SCS line with the HDS.

9.Disconnect PCM connectors A (31P) and C (22P).

10.Measure the resistance between PCM connector terminals C2 and A8 or A9.

 

Is there less than 12 W?


YES - Go to 11.


NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original  PCM.n

11.Disconnect the shift solenoid harness connector at the transmission housing.

12.Check for continuity between PCM connector terminals C2 and A8 or A9.

 

Is there continuity?


YES - Repair short to ground in the wire between PCM connector terminal C2 and the shift solenoid harness connector, then go to 13.


NO - Check shift solenoid valve C, and check for a short in the shift solenoid harness in the transmission. Replace shift solenoid valve C and/or shift solenoid harness, then go to 13.

13.Clear the DTC with the HDS.

14.Start the engine, and shift to the D position.

15.Check the OBD status in DTC Monitor Tool from DTCs/Freeze Data in A/T Mode Menu for a pass/fail test of code P0979.

Did the result indicate a pass?


YES - The problem has been corrected.n


NO - Return to 1 and recheck.n