Voltage on the range sensor B signal line is above the expected window. Wire shorted to B+ or sensor open.
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 or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Most likely causes
- Signal wire shorted to B+
- Open range sensor B
- Connector pins corroded - high contact resistance
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 P2803 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 8: Transmission
- 03: Specific fault in that system
Frequently asked questions
Can I keep driving with code P2803?
Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
What causes code P2803?
The most common causes are: signal wire shorted to B+; open range sensor B; connector pins corroded - high contact resistance.
Related codes
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.