P25A2Brake System Control Module A Requested MIL Illumination
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P25A2 is a messenger code: the brake system control module has stored an emission-relevant fault of its own and asks the engine module to light the check engine lamp. GM's 2017 engine table 17OBDG04 and 2019 hybrid table 19OBDG01 watch this request continuously from three seconds after power-up and class the engine module entry itself as Type A without a separate lamp request, because the lamp is already on the brake module's behalf. GM bulletins show the spread of causes: PIC6404 for 2020 Cadillac CT4 and CT5 links it to lost front camera communication, PIT6012 for 2023 Colorado and Canyon to a weak battery with C05D3 and a spongy pedal. Volvo's technical journal 36899 cures P25A268 on many 2017–2024 models by software. Read the brake module before replacing anything. Brake module B uses P25C9.
- What you may notice
- Check engine lamp on
- ABS, stability or driver assistance warnings at the same time
- Brake pedal may feel soft in some cases
- Likely causes
- LikelyEmission-relevant fault stored in the brake control module
- PossibleWeak battery or low system voltage upsetting the brake module
- PossibleBrake or related module software needing an update
- RareLost communication with a partner module such as the front camera
- 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: €50 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.