P2AD2Throttle/Pedal Position Sensor/Switch B/G Voltage Correlation
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2AD2 sets when signals B and G no longer agree in voltage. On engines with one throttle body per bank this is a cross-bank comparison: with GM's 2023 letter scheme, B is the second track of the bank 1 throttle and G the second track of the bank 2 throttle. Mercedes-Benz uses P2AD2 on its M177 twin-turbo V8 (AMG C63, E63, GLE63, GT63, also GLE/GLS 580 and Maybach GLS 600): the third version (August 2026) of bulletin LI07.10-P-080384 added P2AD200 to its list and traces it, together with P2135, P2136 and P2AD3, to high resistance in the pins of both throttle actuators, left and right; the fix is new silver- and gold-plated terminals and seals. Drivers notice the check engine light and possibly reduced power.
- What you may notice
- Check engine light on
- Possible loss of power
- Further throttle codes such as P2135 or P2136 stored
- Likely causes
- LikelyHigh resistance at the pins of the throttle actuator connectors
- PossibleDrifting position track in one of the throttle bodies
- RareDamaged wiring to one throttle actuator
- 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: €150 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.