P126F Possible Causes
- Faulty nitrogen oxide (NOx) sensor
- Nitrogen oxide (NOx) sensor harness is open or short-circuited
- Poor electrical connection in the nitrogen oxide (NOx) sensor circuit
How is the P126F code repaired?
Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and associated connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Engine light on (or service engine soon warning light)
P126F Meaning
The Engine Control Module (ECM) monitors the nitrogen oxide (NOx) sensor. The ECM sets the OBDII code when the nitrogen oxide (NOx) sensor does not meet factory specifications.