OBD-II code · Powertrain (generic)
P0944 Hydraulic Pressure Unit Loss of Pressure
TCM detects rapid loss of hydraulic pressure in transmission accumulator or main pump circuit.
Is it safe to drive with P0944?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyAccumulator leak
- PossiblePump seal failed
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Repair at a glance
- Difficulty
- Shop_only
- DIY friendly
- Best left to a mechanic
- Typical labour
- 3–12 h
- Emissions test
- Usually unaffected
- Parts involved
- Hydraulic Accumulator, Transmission Pump, Valve Body
Related codes
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.