Network
generic / SAE
U0621
Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 1
The vehicle bus reports loss of communication with smart exhaust gas temperature sensor bank 2 sensor 1 (typically pre-cat). Catalyst protection and DPF regeneration logic switch to model-based estimates.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number6 / 21
Possible causes
- Bus wiring open or shorted high
- Module without power or ground medium
- Module failed medium
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 120–800 €
- Estimated time: 0.5–2 h
- Component: egt sensor bank 2 sensor 1
- Component: vehicle bus wiring
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012