P2C44Battery Isolation/Voltage Stabilization Control Circuit Performance
- Generic OBD-II code · Powertrain
- Can trigger limp mode
- How the car detects it
- P2C44 means the isolation or voltage stabilization stage is wired and commanded, yet its behaviour does not match what the module expects. Ford is the one maker with published cases: 2021–2022 F-150 trucks with the 3.5 L PowerBoost hybrid and 10R80 MHT gearbox carry a second 12 V battery that an auxiliary battery isolator separates from the main battery. Two special service messages (SSM 50843, 50976) have the technician check ground circuit GD132 including G102, C146 and C1989C and test the auxiliary battery before swapping the isolator; bulletin 23-2031 then combined new PCM software with a new isolator (ML3Z-14526-B, up to 0.7 h). Ford shows the wrench indicator rather than the emissions lamp, sometimes together with U061E. Unlike P2C45/P2C46 the wiring voltage itself is not out of range.
- What you may notice
- Wrench (powertrain malfunction) indicator on
- U061E may be stored alongside
- Electrical glitches during engine pull-up
- Likely causes
- LikelyAuxiliary battery isolator faulty (Ford replaces it per bulletin 23-2031)
- LikelyPoor ground in the isolator circuit (Ford GD132, G102, C146, C1989C)
- PossibleOutdated PCM software
- PossibleWeak or failing auxiliary 12 V battery
- Repair
- Medium · Usually a job for a workshop.Typical cost: €100 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.