OBD-II fault code

P07B2: Transmission Park Position Sensor/Switch A Circuit/Open

What it means

The transmission control module detected an open circuit in park position sensor or switch A. The code does not establish the vehicle's park interlock or starting behavior.

At a glance

  • Usually lights the check-engine light

How it works

Park position sensor or switch A reports park-related information to the transmission control module through circuit A. P07B2 sets when the module detects an open circuit in that path, so it cannot rely on a continuous electrical connection; the code alone does not establish how the vehicle will start or behave in Park.

Common causes

Most likely first.

  1. Open wire or unplugged sensor
  2. Pin pushed back out of connector body
  3. Cracked 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

How to diagnose it

  1. Record freeze-frame data and scan transmission live data for the reported state of park sensor or switch A and any related transmission codes.
  2. With the vehicle secured, inspect sensor A's connector and wiring for a disconnected plug, damaged insulation, or a terminal pushed back into the connector.
  3. Trace circuit A between the sensor or switch and the module using the vehicle wiring diagram, looking for a break or poor connection.
  4. With power isolated as specified by the manufacturer, test circuit A for continuity and check its terminals for secure contact.
  5. If wiring and connections pass, test sensor or switch A and the module input according to the manufacturer's procedure before replacing either.

Common fixes

  • Reconnect a loose sensor A plug and secure the harness.
  • Repair a broken wire or restore a backed-out terminal in circuit A.
  • Repair or replace a damaged connector or sensor A with a verified open circuit.
  • Repair the module or sensor solder joint only if testing confirms the internal open.

Can I keep driving?

Because the code does not establish park interlock or starting behavior, verify the vehicle is securely in Park and use the parking brake whenever parked. If gear indication, shifting, or starting behavior is abnormal, avoid driving until it is checked.

A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together

This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.

Codes for the same component

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