P1197moderate severityPowertrain
Downstream O2 Sensor Slow During Catalyst Monitor
on 2007 Ram 3500 5.9L I6 Cummins · 4WD
What this code means
The downstream oxygen sensor responded too slowly during the catalyst monitor test. Related to generic P0139 for O2 sensor response.
Symptoms
- Check engine light on
- Failed emissions test
- Slightly reduced fuel economy
Common causes
- Aged downstream O2 sensor
- Exhaust leak near sensor
- Contaminated sensor
- Wiring fault
Diagnostic steps
- Scan for stored codes
- View downstream O2 waveform
- Check for exhaust leaks
- Replace O2 sensor if slow
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1