For your transmission to perform a gear shift, a small piston-like device called a solenoid opens or closes to direct pressurized transmission fluid into the correct channel, where it pushes or otherwise moves parts such as clutches or gears. If the F shift solenoid (i.e., the sixth solenoid) does not operate according to the programmed parameters, a DTC P0997 will be stored.
How severe is the code?
The diagnostic code P0997 only triggers when the ECU detects that a shift solenoid is not functioning properly. This can lead to a number of driving issues that will eventually result in a non-functional transmission.
Symptoms
Symptoms of a P0997 include:
- The transmission seems to engage
- The gearbox will not shift into or out of gear
Causes
- There is not enough transmission fluid
- The transmission fluid is dirty/thin
- Damaged/broken wires
- Broken/corroded connectors
- Failed shift solenoid
How to diagnose the code?
The first thing to do when trying to determine what is causing an OBDII fault code P0997 is to check the level and condition of the transmission fluid. If it is too low or dirty, the transmission fluid must be changed. If there are no issues with the condition of the transmission fluid, then the wiring and connectors along the transmission wiring harness should be inspected. If no problems are detected there, the shift solenoid itself must be tested.
What repairs will fix P0997?
- Service the transmission
- Replace or repair damaged wires/connectors
- Replace the shift solenoid