P07BBTransmission Park Position Sensor/Switch B Circuit Performance/Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- With electronic gear selection the park position sensor/switch reports the park request or position. On GM's shift-by-wire selectors (2017 LaCrosse, XT4/XT5, Bolt EV, later SUVs and pickups) it is the P button, read by two redundant analog sensors A and B with separate 'released' and 'pressed' voltage zones. P07BB means sensor B reads in the band between its 'released' and 'pressed' zones (53.2–73.7 % of 5 V, ICCM 45–58 %), checked only when P07B9/P07BA are not set, after two trips. GM's 2017 bulletin also lists it for a knob not fully seated or a connector not latched. No other manufacturer is documented.
- What you may notice
- Check engine light, 'service transmission' or 'unable to shift' message
- Park cannot be selected by button, or the car will not shift out of P
- P button illumination off
- Likely causes
- LikelyP button sensor faulty or worn
- PossibleKnob not seated, button sticking
- PossibleContact resistance in the connector
- RareModule software
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.