OBD-II code · Powertrain (generic)
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.
Is it safe to drive with P07B8?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen wire or unplugged sensor
- Less likelyPin pushed back out of connector body
- Less likelyCracked solder joint inside the module or sensor
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
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–2 h
- Emissions test
- Usually unaffected
- Parts involved
- Park Position Sensor B, Wiring Harness
Related codes
- P07B2Transmission Park Position Sensor/Switch A Circuit/Open
- P07B5Transmission Park Position Sensor/Switch A Circuit Performance/Low
- P07B6Transmission Park Position Sensor/Switch A Circuit Performance High
- P07B7Transmission Park Position Sensor/Switch A Circuit Intermittent/Erratic
- P07B9Transmission Park Position Sensor/Switch B Circuit Low
- P07BATransmission Park Position Sensor/Switch B Circuit High
- P07BBTransmission Park Position Sensor/Switch B Circuit Performance/Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.