Gear lever X and Y position sensors detect a selector's position in two directions: on an H-gate shift and select direction (a LuK patent uses two sensors about 90° apart), on a shift-by-wire lever its two axes. P0820 covers the whole X-Y circuit, P0821–P0824 and P082A–P082F sensor 1, P089A–P08A3 a redundant sensor 2. GM uses P082A–P082F on its electronic range selector (2019 tables, Cadillac XT4, 2025): a Hall sensor delivers a PWM signal, measured as duty cycle. P082B means the duty cycle of X sensor 1 is too low – the signal stays near 0 %, a short to ground or a sensor without supply. GM sets it below 17 % with 3 of 4 samples of 25 ms (2019) or below 5 % with 10 of 12 samples (2025), type B with the MIL after two trips. Sensor 2 then takes over; if both fail, park is selected, as GM's patent describes.
Medium severity. Can I keep driving?Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
Symptoms
- Check engine lamp after two trips (GM)
- 'Shift to park' message or transmission warning
- Range selection restricted; with both sensors failed the vehicle goes to park
Most likely causes
- Signal wire shorted to ground
- Sensor supply open
- Sensor in the selector assembly faulty
- Control module
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It can trigger limp mode.
What each character of P082B means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 8: Transmission
- 2B: Specific fault in that system
Frequently asked questions
Can I keep driving with code P082B?
Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
What causes code P082B?
The most common causes are: signal wire shorted to ground; sensor supply open; sensor in the selector assembly faulty.
Related codes
- P082AGear Lever X Position Sensor 1 Circuit Range/Performance
- P082CGear Lever X Position Sensor 1 Circuit High
- P082EGear Lever Y Position Sensor 1 Circuit Low
- P0821Gear Lever X Position Sensor 1 Circuit
- P0823Gear Lever X Position Sensor 1 Circuit Intermittent/Erratic
Sources
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.