No signal activity from the upstream Bank 2 O2 sensor.
SYMPTOMS
- Check-engine light
- Economy loss
LIKELY CAUSES
- Dead O2 sensor
- Open wiring
- Failed heater
- Exhaust leak
DIAGNOSIS STEPS
- Check signal and heater
- Test wiring
- Inspect exhaust
- Replace sensor
RELATED PARTS
- Upstream O2 sensor (Bank 2)