P0997: Shift Solenoid 'F' Control Circuit Range/Performance
The Powertrain Control Module (PCM) has detected that the shift solenoid 'F' control circuit is operating outside its expected range or performance parameters. This solenoid is typically part of the transmission valve body and controls hydraulic pressure for gear engagement. The code indicates an electrical or mechanical issue affecting solenoid operation, which can lead to improper shifting or transmission slippage.
01. Most Common Causes
- Faulty shift solenoid 'F'
- Wiring or connector issues in the solenoid circuit (open, short, or high resistance)
- Low transmission fluid level or dirty fluid
- Internal transmission mechanical failure
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Harsh or erratic shifting
- Transmission slipping or delayed engagement
- Reduced fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan the vehicle for additional codes and record freeze frame data.
Step 2: Inspect transmission fluid level and condition; top off or replace if necessary.
Step 3: Visually check wiring and connectors for damage, corrosion, or loose connections.
Step 4: Test solenoid resistance and power/ground circuits with a multimeter; compare to manufacturer specs.
Step 5: If electrical tests pass, perform a transmission pressure test or solenoid actuation test using a scan tool.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the transmission may shift erratically or fail, potentially causing a safety hazard. Have the vehicle inspected promptly.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, including parts and labor. If the solenoid is internal, labor costs may be higher due to transmission disassembly.