B0425Audio Amplifier Internal Failure
- Generic OBD-II code · Body
- How the car detects it
- Every accessible J2012 list lacks B0425, and no maker's literature mentions it, leaving the code itself unverified. The title concerns a fault inside the separate audio amplifier rather than in its wiring. Amplifier chips such as TI's TAS6424E-Q1 check each channel for open load, shorted load and shorts to battery or ground, and raise a warning on clipping or overtemperature. In GM's Global A electronics, as fitted to 2011 Saab 9-5 and 9-4X cars, the amplifier stores no codes of its own; the radio watches the PWM mute line and logs B1287 if that line is open or shorted 0.4 s after it switches the amplifier on. Typical signs are silence or crackling on all amplified channels. Communication loss with the amplifier is U0186, a fault of the head unit B0420.
- What you may notice
- No sound or only very low volume from the amplified speakers
- Crackling, hum or distortion, often worse when warm
- Subwoofer or premium sound channels drop out
- Likely causes
- LikelyOutput stage or internal electronics of the amplifier failed
- PossibleAmplifier overheated, e.g. under a seat or in the boot without airflow
- PossibleMoisture or water in the amplifier housing or plug
- RareShorted speaker or wiring that has overloaded the output stage
- Repair
- Medium · Usually a job for a workshop.Typical cost: €150 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.