What it means
General electrical fault on the transmission range display circuit — drives the PRNDL indicator on the dashboard. With the input invalid the indicator may show the wrong gear range or stay blank.
How it works
The transmission range display circuit provides the dashboard with the selected range indication, commonly shown as P, R, N, and D. The system monitors the display circuit and sets P0814 when it detects an electrical fault that can leave the indicator blank or incorrect. This code concerns the range display circuit and does not by itself prove that the transmission is in the displayed range.
Common causes
Most likely first.
- Open circuit in range display wiring
- Short to ground or power in the display circuit
- Loose or corroded connector
- Faulty range display or indicator
- Control module circuit fault
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
- Save freeze-frame data and check for related transmission codes, then compare the dashboard range display with the actual selector position while the vehicle is secured.
- Inspect the range display, its connector, and accessible wiring for damage, loose connections, or corrosion.
- Check the display circuit for opens and shorts to ground or power using the manufacturer's wiring information and test procedure.
- Test the range display or indicator and its signal input according to the manufacturer's specification.
- If the display and wiring pass, check module connectors, power, grounds, and the relevant output circuit.
Common fixes
- Repair an open or shorted range display wire.
- Clean or repair loose, corroded, or damaged connectors.
- Replace a faulty transmission range display or indicator after confirming it fails testing.
- Repair a module circuit fault only after the display and wiring pass.
Can I keep driving?
Do not rely on a blank or incorrect dashboard range indication when selecting gears; confirm the vehicle is in the intended range before moving. If the actual gear engagement is also uncertain, do not drive 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.