P07BB code meaning
Transmission Park Position Sensor/Switch B Circuit Performance/Low
Powertrain system Generic code P07xx codes Check engine light
What P07BB means
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.
P07BB at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P07BB
- 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
Common causes of P07BB
- Most likelyP button sensor faulty or worn
- PossibleKnob not seated, button sticking
- PossibleContact resistance in the connector
- Less likelyModule software
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Park position sensorElectronic range selectorSensor wiringTransmission control module
What each part of P07BB means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 7 | Area: transmission. |
| BB | The exact fault in that area. |
What to do next
- Note P07BB and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P07BB
What does P07BB mean?
P07BB means "Transmission Park Position Sensor/Switch B Circuit Performance/Low". With electronic gear selection the park position sensor/switch reports the park request or position. It is a generic code, so it means the same on every make.
Is it safe to drive with P07BB?
Drive gently and only to a workshop. With P07BB the car can go into limp mode (reduced power) to protect itself.
Will P07BB fail an emissions test?
P07BB is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P07BB to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P07BB clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.