C0161ABS/TCS Brake Switch Circuit
- Generic OBD-II code · Chassis
- Needs a drive cycle to confirm a fix
- How the car detects it
- C0161 is outside the accessible J2012 tables but well documented at GM. Service data for the later Saab 9-5 and the 9-4X define it as an implausible ABS brake switch signal: the EBCM receives the pedal-applied message from the body module and compares it with brake pressure and vehicle motion. The 9-4X sets it after four starts to over 40 km/h without any switch change, or when the pedal reads applied for 360 s above 20 km/h with less than 15 bar; the 9-5 uses 122 s and 6.2 bar plus a check for more than 15 bar for 2 s with the pedal released. GM bulletin PIT5181A for 2012–2014 full-size trucks and SUVs links C0161 and C0277 to a loose terminal in connector X205. Hill start assist may be disabled; braking while accelerating can also set it.
- What you may notice
- Service stability or traction message
- Cruise control or brake lights may misbehave
- Hill start assist unavailable
- Likely causes
- LikelyBrake pedal position sensor or switch out of adjustment
- PossibleLoose or backed-out terminal in the pedal sensor wiring (GM X205)
- RareBrake applied while accelerating (left-foot braking)
- RareBrake pressure sensor reading that contradicts the pedal signal
- Repair
- Easy · Often possible to do yourself.Typical cost: €0 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.