P24F1Control Module Wake-up Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- With P24F1 the wake-up line carries voltage while its driving module has the output switched off, so a short to a battery feed or a second source keeps it live. GM's HPC2 module in the 2016 and 2019 hybrid tables flags 13.21 V or more in the off state, using the same 480-of-560 sample count at 12.5 ms and Type A, MIL after one trip. Mercedes-Benz documents P24F100 in the 8-speed dual-clutch gearbox controller of CLA, GLA and GLB (XENTRY tip LI27.19-P-080869, 2026): the wake line appears shorted to positive, the car may briefly refuse to start, and the cause is signal timing with the ignition switch module, fixed by new SCN coding of that unit. P24EF is open, P24F0 low.
- What you may notice
- Check engine light and several warning messages
- Temporary no-start condition
- Possible battery drain while parked
- Likely causes
- LikelyWake-up line shorted to a battery feed
- PossibleSignal timing between ignition module and receiving unit, solved by coding
- RareVoltage fed back from another module that stays awake
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.