Skip to content

Chassis

C121D

Code meaning and manufacturer information

OBD-II / DTC

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

1

Original wording in English

View all ↗

PIT4593D ↗

CADILLAC, CHEVROLET, GMC

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 Antilock Braking System Malfunction Indicator Lamp may also be on. Technician may find Diagnostic Trouble Code…

Check vehicle applicability

38

A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

View all ↗

MakeModelModel year
CadillacESCALADE ↗2013
CadillacESCALADE ↗2012
CadillacESCALADE ↗2011
CadillacESCALADE ↗2010
CadillacESCALADE ↗2009
ChevroletSILVERADO ↗2013
ChevroletSILVERADO ↗2012
ChevroletSILVERADO ↗2011

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.