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.
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
C0378FRONT AXLE SWITCH CIRCUIT SIGNAL INVALIDC0378FRONT AXLE SWITCH CIRCUIT SIGNAL INVALIDManufacturer communications
2Original wording in English
CHEVROLET, GMC
Reported code forms C0378
INTERMITTENT/INOPERATIVE FOUR WHEEL DRIVE, SERVICE 4WD SYSTEM LAMP ON AND DTC C0378 - FRONT AXLE SWITCH CIRCUIT SIGNAL INVALID. *KB
CHEVROLET, GMC
Reported code forms C0378
INTERMITTENT SERVICE 4 WHEEL DRIVE LAMP ON AND CODE C0378. *KB UPDATED 10/03/07. *NJ
Check vehicle applicability
7A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Chevrolet | AVALANCHE 1500 | 2007 |
| Chevrolet | AVALANCHE 2500 | 2007 |
| Chevrolet | SUBURBAN 1500 | 2007 |
| Chevrolet | TAHOE | 2007 |
| GMC | YUKON | 2007 |
| GMC | YUKON XL 1500 | 2007 |
| GMC | YUKON XL 2500 | 2007 |
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.
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.