Powertrain, generic · Transmission

P07B2 Transmission Park Position Sensor/Switch A Circuit/Open

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

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. P07B2 means the circuit of sensor A is open: the module sees a missing or undefined signal. No manufacturer document available to us uses this code; GM covers an open analog circuit under its low and high codes (P07B3/P07B4), which CARB allows when an open cannot be told apart from an out-of-range value. Park may then not be selectable by button.

Likely causes

Wire or connector to the selector open
Connector not latched
Sensor faulty

Symptoms

  • 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

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

park position sensorelectronic range selectorsensor wiringtransmission control module

Related codes

P07B3P07B4P07B7P07B8P07BEP0705

References: law.cornell.edu, gsi.ext.gm.com.