P2C48Coolant Pump C Control Circuit Performance/Stuck Off
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2C48 is a performance check on coolant pump C: the pump is driven, but what it draws or delivers does not match the request. GM uses it in its diesel tables, where pump C is the electric pump of the low-temperature loop: 20OBDG04 estimates the phase current expected at the actual pump speed and flags an error above 4 A for more than 5 s (5 failures in 8 samples), 25OBDG04A above 1 A with the pump over 2,800 rpm (10 of 12); both type B, two trips. In 19OBDG07 GM assigns P2C48 to the pump for the charge air cooler, using a speed-dependent current window. Bulletin 21-NA-265 (Silverado/Sierra 2500/3500 HD 2020–2022, L5P) links P2C48 and a coolant leak to the fuel cooler hose rubbing on the front drive shaft. Underspeed is P2BA0.
- What you may notice
- Check engine light after two trips
- Coolant leak under the vehicle
- Higher intake air or fuel temperature, possibly reduced power
- Likely causes
- LikelyLow coolant or air in the low-temperature loop, e.g. from a chafed hose (GM 21-NA-265)
- PossibleWorn, sluggish or partly blocked pump
- PossibleFault in the pump's integrated motor electronics
- RareWeak supply from the powertrain relay or poor ground
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.