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 communications
1Original wording in English
CADILLAC, CHEVROLET, GMC
Reported code forms C121D
This Preliminary Information communication provides information to the technician about vehicles that have a lack of brake assist after disconnecting the battery or after the 12 volts battery has run low on voltage. The…
Check vehicle applicability
38A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Cadillac | ESCALADE | 2013 |
| Cadillac | ESCALADE | 2012 |
| Cadillac | ESCALADE | 2011 |
| Cadillac | ESCALADE | 2010 |
| Cadillac | ESCALADE | 2009 |
| Chevrolet | SILVERADO | 2013 |
| Chevrolet | SILVERADO | 2012 |
| Chevrolet | SILVERADO | 2011 |
| Chevrolet | SILVERADO | 2010 |
| Chevrolet | SILVERADO | 2009 |
| Chevrolet | TAHOE | 2013 |
| Chevrolet | TAHOE | 2012 |
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.