What it means
The control module detects a high electrical level in the shift solenoid C control circuit.
At a glance
- Usually lights the check-engine light
How it works
Shift solenoid C is an electrically operated valve that controls transmission fluid flow during certain shifts. The transmission control module monitors the C solenoid control signal and sets P0980 when it sees an electrical level higher than expected, which can result from a short to battery voltage or a poor connection.
Common causes
Most likely first.
- Short to battery
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Use freeze-frame and transmission live data to identify when P0980 occurs, and check for related solenoid C or supply-voltage codes.
- Inspect the C solenoid connector and harness for corrosion, pin damage, or wiring pinched against a battery-positive source.
- With the circuit isolated as directed by the manufacturer, check shift solenoid C coil resistance and compare it with the manufacturer's specification.
- Test the C control wire for a short to battery voltage and check connector contact condition, including any high-resistance corrosion.
- If the wiring and solenoid pass, verify the control module connector and C circuit output before considering a module fault.
Common fixes
- Clean or repair corroded terminals in the shift solenoid C circuit.
- Repair wiring shorted to battery voltage or pinched against a power source.
- Replace shift solenoid C if its coil fails the manufacturer's test.
- Repair a confirmed control module connector or circuit fault.
Can I keep driving?
If shifts are harsh, delayed, or slipping, keep driving to a minimum and avoid towing or hard acceleration. A high C circuit signal can disrupt shifting and continued slipping can damage the transmission; stop if it enters limp mode or becomes unpredictable.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.