P07B8 — Transmission Park Position Sensor/Switch B Circuit/Open
Park position sensor/switch B is the redundant/secondary park-confirmation sensor — used in shift-by-wire systems for safety, so a single sensor failure cannot strand the vehicle in Park or hide a non-Park condition. With B open the TCM falls back to sensor A only.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Park position sensor b
- Wiring harness
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Open wire or unplugged sensor
- Pin pushed back out of connector body
- Cracked solder joint inside the module or sensor
Possible symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.