P11CB GMC Possible Causes
- Faulty NOx sensor 1
- NOx sensor 1 harness is open or shorted
- Poor electrical connection in NOx sensor 1 circuit
- Intake system leaks
- Exhaust system leaks
How is GMC P11CB Code Repaired?
Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Engine light on (or engine service soon warning light)
P11CB GMC Meaning
The Powertrain Control Module (PCM) monitors NOx sensor 1. The PCM sets the OBDII code when NOx sensor 1 does not meet factory specifications.