P0943high severityPowertrain
Hydraulic Pressure Unit Cycling Period Too Short
on 2007 Ram 3500 5.9L I6 Cummins · 4WD
What this code means
The transmission hydraulic pressure accumulator is cycling on and off too frequently. This often points to a leak in the hydraulic system or a failing pump that can't hold pressure.
Symptoms
- Harsh or erratic shifting
- Transmission warning light on
- Whining noise from transmission
Common causes
- Internal transmission fluid leak
- Faulty hydraulic pump
- Worn accumulator or seals
- Low transmission fluid level
Diagnostic steps
- Check transmission fluid level and condition
- Scan for related transmission codes
- Test hydraulic system pressure
- Inspect pump and accumulator for wear or leaks
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1