P1780moderate severityPowertrain
Modulating Pressure Switchover Valve
on 2002 Mercedes-Benz SL 3.0L I6 · RWD
What this code means
The ECU detected a fault in the transmission modulating pressure switchover valve. This valve controls transmission line pressure modulation for smooth shift quality.
Symptoms
- Check Engine Light
- Harsh shifts
- Delayed engagement
- Transmission slip during shifts
Common causes
- Faulty modulating pressure valve
- Valve body solenoid failure
- Wiring fault
- Dirty transmission fluid affecting valve
- Low transmission fluid level
Diagnostic steps
- Test switchover valve solenoid resistance
- Monitor transmission pressure with scan tool
- Inspect valve body for contamination
- Check transmission fluid level and condition
- Test wiring to solenoid
Repair notes
Replace the modulating pressure switchover valve or clean the valve body.
Other Powertrain codes on this vehicle
P0001
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P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
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P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1