Reference meaning
What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Narrow by vehicle
A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Scan worksheet →Manufacturer communications
1Original wording in English
FORD, LINCOLN
THIS ARTICLE ADDRESSES THE PROPER PROCEDURE TO CLEAR DIAGNOSTIC TROUBLE CODES C1990 OR C1991 FROM THE VEHICLE DYNAMICS MODULE/4-WHEEL AIR SUSPENSION MODULE. *TT
Check vehicle applicability
2A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Ford | EXPEDITION ↗ | 2003 |
| Lincoln | NAVIGATOR ↗ | 2003 |
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.