DTC P0979: Short in Shift Solenoid Valve C Circuit

WARNING: This page is about a different variant/trim than selected.

NOTE:

Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information (see GENERAL TROUBLESHOOTING INFORMATION ).
This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
If DTC P0979 is stored in the PCM, the transmission does not shift to 2nd or 5th gear because of the fail-safe function.

Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
Clear the DTC with the HDS.
Start the engine in P, and wait for at least 1 second.
Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0979 indicated?

YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for poor connections and loose terminals between shift solenoid valve C and the PCM.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
Check for a blown No. 10 (10 A) fuse in the driver's under-dash fuse/relay box.
Is the No. 10 (10 A) fuse OK?

YES - Go to step 7.

NO - Repair a short to body ground in the wire between PCM connector terminal A1 and the driver's under-dash fuse/relay box.
Jump the SCS line with the HDS.
Disconnect PCM connectors A (49P).
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
Measure the voltage between PCM connector terminals A1 and body ground.

Fig 1: Measuring Voltage Between PCM Connector Terminals A1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Go to step 11.

NO - Repair an open in the wire between PCM connector terminal A1 and the driver's under-dash fuse/relay box.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
Disconnect the shift solenoid valve C connector.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
Clear the DTC with the HDS.
Start the engine in P, and wait for at least 1 second.
Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0979 indicated?

YES - Go to step 17.

NO - Replace shift solenoid valve C (see SHIFT SOLENOID VALVE C TEST AND REPLACEMENT ).
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
Jump the SCS line with the HDS.
Disconnect PCM connector C (49P).
Check for continuity between PCM connector terminals C9 and body ground.

Fig 2: Checking Continuity Between PCM Connector Terminals C9 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair a short to body ground in the wire between PCM connector terminal C9 and shift solenoid valve C connector terminal No. 2.

NO - Replace the PCM (see ECM/PCM REPLACEMENT ).