Diesel Data: Automotive Repair

Advanced Diagnostics




DTC P2195 (155) Advanced Diagnostics

DTC P2195:

Rear Air/Fuel Ratio (A/F) Sensor (Bank 1, Sensor 1) Signal Stuck Lean





General Description

When the rear air/fuel ratio (A/F) sensor (bank 1, sensor 1) is properly connected to the engine wire harness, but it is not installed in the exhaust pipe, the feedback is not done properly even if the rear A/F sensor (bank 1, sensor 1) is active after starting the engine. Thus, the exhaust emissions increase. When the rear A/F sensor (bank 1, sensor 1) output stays out of the normal range after the rear A/F sensor (bank 1, sensor 1) becomes active, the powertrain control module (PCM) detects that the rear A/F sensor (bank 1, sensor 1) is not properly installed and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status





Enable Conditions





Malfunction Threshold

The rear A/F sensor (bank 1, sensor 1) output voltage is 3.48 V or more for at least 7.0 seconds.

Driving Pattern

Start the engine, and let it idle for at least 2 minutes.

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.