OBD-II code · Powertrain (generic)
P07B9 Transmission Park Position Sensor/Switch B Circuit Low
Park sensor/switch B reads stuck low — short to ground or stuck-closed contact. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Is it safe to drive with P07B9?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyWire shorted to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
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
Related codes
- P07B3Transmission Park Position Sensor/Switch A Circuit Low
- P07B8Transmission Park Position Sensor/Switch B Circuit/Open
- P07B6Transmission Park Position Sensor/Switch A Circuit Performance High
- P07B7Transmission Park Position Sensor/Switch A Circuit Intermittent/Erratic
- P07BATransmission Park Position Sensor/Switch B Circuit High
- P07BBTransmission Park Position Sensor/Switch B Circuit Performance/Low
- P07BCTransmission Park Position Sensor/Switch B Circuit Performance High
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.