Code
P0797
Generic
P — Powertrain
Pressure Control Solenoid C Stuck On
Views:
UK: 21
EN: 25
RU: 29
AI status
Completed
Completed
100%
Causes
- Internal solenoid coil failure (shorted/stuck)
- Short to voltage on solenoid control circuit
- Short to ground on solenoid control circuit
- Poor connector or wiring (corrosion, breaks, chafing)
- Contaminated/dirty transmission fluid or debris in valve body
- Faulty transmission control module (TCM) / PCM
Symptoms
- Check Engine Light / MIL illuminated
- Erratic or harsh shifting
- Delayed engagement or inability to shift properly
- Transmission may enter limp/limitation mode
- Unusual transmission behavior (slip, surge) under load
- Possible reduced fuel economy or loss of drive
What to check
- Scan for stored freeze frame and related transmission codes
- Visual inspection of transmission connector and wiring for damage or corrosion
- Check transmission fluid level, color, and smell (burnt or contaminated fluid)
- Measure solenoid coil resistance with multimeter and compare to spec
- Backprobe control wire with ignition ON and/or while commanded to operate to check voltage/PWM
- Use scan tool to command solenoid ON/OFF and observe response
Signal parameters
- Coil resistance: typically 10-30 ohms (varies by manufacturer) — compare to OEM spec
- Control signal: PWM duty cycle 0–100% when commanded (varies by application)
- PWM frequency: commonly 20–200 Hz (application dependent)
- Control circuit voltage (key ON, engine OFF): approx. battery voltage on feed; switch side may be ground-switched
- Current draw when energized: typically
Diagnostic algorithm
- Retrieve freeze frame and all stored codes. Note operating conditions when the code set.
- Perform a visual inspection of the transmission harness, connector, and solenoid connector for corrosion, loose pins, or damage.
- Check ATF level and condition. If fluid is low or contaminated, correct fluid issues and clear codes to retest.
- Disconnect the solenoid connector and measure coil resistance across the solenoid terminals. Compare to spec. An open or short indicates solenoid fault.
- With connector disconnected, check for voltage on the reference feed and for short to ground on the control side (use backprobe): unplugged, battery voltage should be present on feed circuit; control circuit should be open or show expected resting voltage.
- Reconnect and use a scan tool to command Pressure Control Solenoid C ON and OFF while observing the control circuit with a scope or duty-cycle-capable meter. Verify PWM frequency and duty change when commanded.
- If commanded state does not change or circuit shows stuck-on voltage/duty, trace wiring for short to battery or to ground using wiring diagrams. Repair damaged wiring/connectors.
- If wiring and PCM outputs test good but solenoid is abnormal, replace solenoid assembly (or valve body if required). Clean valve body if contamination is present.
- After repair, clear codes and road test under the same conditions that caused the code to confirm repair. Re-scan for persistent or related codes.
- If symptoms persist and electrical and hydraulic checks pass, consider TCM/PCM diagnostics and reprogramming or replacement per manufacturer procedures.
Likely causes
- Failed pressure control solenoid C (most common)
- Wiring harness shorted to ground or battery at solenoid circuit
- Poor connector/corrosion at transmission harness connector
- Debris or varnish causing valve body spool to stick
- Low/old/contaminated ATF causing incorrect pressure or sticking
Fault status
Status
Powertrain control module reports Pressure Control Solenoid C stuck ON — control circuit indicates solenoid is energized when it should not be. May set MIL and limit transmission performance until repaired.
Repair difficulty: Medium
Diagnostic time: 1.0 - 3.0 hours
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Code
P0797
LAND ROVER
P — Powertrain
Pressure control solenoid C stuck in
Views:
UK: 5
EN: 9
RU: 19
AI status
Completed
Completed
100%
Causes
- Internal solenoid coil failure (shorted/stuck)
- Short to voltage on solenoid control circuit
- Short to ground on solenoid control circuit
- Poor connector or wiring (corrosion, breaks, chafing)
- Contaminated/dirty transmission fluid or debris in valve body
- Faulty transmission control module (TCM) / PCM
Symptoms
- Check Engine Light / MIL illuminated
- Erratic or harsh shifting
- Delayed engagement or inability to shift properly
- Transmission may enter limp/limitation mode
- Unusual transmission behavior (slip, surge) under load
- Possible reduced fuel economy or loss of drive
What to check
- Scan for stored freeze frame and related transmission codes
- Visual inspection of transmission connector and wiring for damage or corrosion
- Check transmission fluid level, color, and smell (burnt or contaminated fluid)
- Measure solenoid coil resistance with multimeter and compare to spec
- Backprobe control wire with ignition ON and/or while commanded to operate to check voltage/PWM
- Use scan tool to command solenoid ON/OFF and observe response
Signal parameters
- Coil resistance: typically 10-30 ohms (varies by manufacturer) — compare to OEM spec
- Control signal: PWM duty cycle 0–100% when commanded (varies by application)
- PWM frequency: commonly 20–200 Hz (application dependent)
- Control circuit voltage (key ON, engine OFF): approx. battery voltage on feed; switch side may be ground-switched
- Current draw when energized: typically
Diagnostic algorithm
- Retrieve freeze frame and all stored codes. Note operating conditions when the code set.
- Perform a visual inspection of the transmission harness, connector, and solenoid connector for corrosion, loose pins, or damage.
- Check ATF level and condition. If fluid is low or contaminated, correct fluid issues and clear codes to retest.
- Disconnect the solenoid connector and measure coil resistance across the solenoid terminals. Compare to spec. An open or short indicates solenoid fault.
- With connector disconnected, check for voltage on the reference feed and for short to ground on the control side (use backprobe): unplugged, battery voltage should be present on feed circuit; control circuit should be open or show expected resting voltage.
- Reconnect and use a scan tool to command Pressure Control Solenoid C ON and OFF while observing the control circuit with a scope or duty-cycle-capable meter. Verify PWM frequency and duty change when commanded.
- If commanded state does not change or circuit shows stuck-on voltage/duty, trace wiring for short to battery or to ground using wiring diagrams. Repair damaged wiring/connectors.
- If wiring and PCM outputs test good but solenoid is abnormal, replace solenoid assembly (or valve body if required). Clean valve body if contamination is present.
- After repair, clear codes and road test under the same conditions that caused the code to confirm repair. Re-scan for persistent or related codes.
- If symptoms persist and electrical and hydraulic checks pass, consider TCM/PCM diagnostics and reprogramming or replacement per manufacturer procedures.
Likely causes
- Failed pressure control solenoid C (most common)
- Wiring harness shorted to ground or battery at solenoid circuit
- Poor connector/corrosion at transmission harness connector
- Debris or varnish causing valve body spool to stick
- Low/old/contaminated ATF causing incorrect pressure or sticking
Fault status
Status
Powertrain control module reports Pressure Control Solenoid C stuck ON — control circuit indicates solenoid is energized when it should not be. May set MIL and limit transmission performance until repaired.
Repair difficulty: Medium
Diagnostic time: 1.0 - 3.0 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email