OBD-II code · Powertrain (generic, extended)

P2803 Transmission Range Sensor B Circuit High

Voltage on the range sensor B signal line is above the expected window. Wire shorted to B+ or sensor open.

Is it safe to drive with P2803?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelySignal wire shorted to B+
  • PossibleOpen range sensor B
  • Less likelyConnector pins corroded - high contact resistance

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
1–4 h
Emissions test
Usually unaffected
Parts involved
Transmission Range Sensor B, Wiring Harness, Tcm

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.