What this code means
P0980 generally means the control circuit for shift solenoid valve C may be open or not responding electrically as expected.
What the vehicle may do
- The vehicle may go into transmission fail-safe operation.
- The driver may notice missing shifts, abnormal shift timing, or limited gear operation.
- The concern can be intermittent if the circuit connection only opens under certain conditions.
Possible fault areas
- Possible ignition feed or fuse issue
- Possible open wiring in the solenoid control or feed circuit
- Possible poor ground or connector terminal issue
- Possible shift solenoid valve C electrical fault
- Possible PCM-side circuit fault
Diagnostic path
Open and frame the fault
For P0980 on this 2010 to 2017 Honda Accord with the 2.4 gas engine, think of this as an electrical open fault in the shift solenoid valve C control circuit. The car may be in fail-safe and may have missing or abnormal shifts, and the broad fault areas are the solenoid circuit feed, the fuse, wiring, ground, the solenoid itself, or the PCM side of the circuit. One important point before testing: this code is called out as an electrical circuit problem, not a mechanical transmission problem. Also, if P0980 is stored in the PCM, the transmission does not shift to 2nd or 5th gear because of fail-safe operation. Before clearing anything, save the freeze data and any on-board snapshot with the HDS so you know the conditions you are trying to duplicate.
Verify the code first
Start with the basic system checks, then verify the fault. Select ON mode with the engine start/stop button, clear the code with the HDS, and start the engine. With the brake pedal pressed, shift to N or D and wait for at least 1 second. Then check pending and confirmed codes with the HDS. If P0980 comes right back, the failure is duplicated and you move into circuit testing. If it does not come back, treat it as intermittent. At that point, inspect for poor connections and loose terminals in the shift solenoid valve C circuit, and do not guess past the confirmed path.
Check the solenoid feed fuse
Next, turn the vehicle OFF and check fuse No. B8, rated at 10 A, in the under-dash fuse and relay box. If the fuse is OK, continue to the feed-side voltage check. If the fuse is blown, replace the No. B8 10 A fuse and recheck. If it blows again, repair the short to body ground on that fuse circuit before going any farther.
Check the IG1 MISS SOL feed wire
Now check for an open on the IG1 MISS SOL line. Jump the SCS line with the HDS, disconnect PCM connector A, the 51-pin connector, then select ON mode. Measure voltage between PCM connector A terminal No. 1, the light blue wire, and body ground. Under that test condition, you are looking for battery voltage. If battery voltage is present, that feed wire is OK and you move on. If battery voltage is not present, repair the open in the IG1 MISS SOL wire between the PCM and the No. B8 10 A fuse in the under-dash fuse and relay box.
Use the companion circuit response to split the path
After the feed checks good, turn the vehicle OFF and reconnect PCM connector A. Disconnect the shift solenoid valve C 2-pin connector. Ground terminal No. 1, the green wire, at the solenoid connector with a jumper wire. Then select ON mode, clear the code with the HDS, start the engine in Park, and wait for at least 1 second. Check pending and confirmed codes again. If the expected companion circuit response shows up, go to the solenoid and ground-side continuity check. If it does not show up, skip ahead to the SHC wire continuity check.
Check solenoid C ground continuity
For the solenoid-side branch, turn the vehicle OFF and remove the jumper wire. With the shift solenoid valve C 2-pin connector disconnected, check continuity between connector terminal No. 2, the black wire, and body ground. If there is continuity, the diagnostic path calls for replacing shift solenoid valve C. If there is no continuity, the solenoid is considered OK on this path, and the repair is an open in the PG wire between the PCM and body ground G101, or a poor body ground at G101.
Check the SHC control wire
If the earlier split sends you to the SHC line, turn the vehicle OFF and make sure the jumper wire is removed. Jump the SCS line with the HDS, disconnect PCM connector B, the 51-pin connector, and check continuity between shift solenoid valve C connector terminal No. 1, the green wire, and PCM connector B terminal No. 3, also the green wire. If there is no continuity, repair the open in the SHC wire between shift solenoid valve C and the PCM. If there is continuity, the SHC wire is OK and the diagnostic path calls for PCM replacement.
Takeaway and close
The clean way through P0980 is to prove the code first, confirm the 10 A feed fuse and feed voltage, then use the solenoid C connector checks to separate a solenoid or ground problem from an SHC control-wire or PCM-side problem. Keep it electrical, keep it in order, and recheck after the repair instead of jumping straight to parts. For more diagnostic training, visit stepdiagnostics.com.
Final check
This diagnosis is primarily an electrical circuit isolation process, not a mechanical transmission teardown path.
For more guided automotive diagnostics, visit STEP Diagnostics.
