(P0137) 02 Sensor 1/2 Below Threshold

(P0137) 02 SENSOR 1/2 BELOW THRESHOLD






When Monitored and Set Condition
^ When Monitored: Start and drive vehicle greater than 32 km/h (20 MPH) and less than 89 km/h (55 MPH). Throttle open for a minimum 120 seconds. Coolant Temp greater than 70 °C (158 °F) and Catalytic Converter Temperature greater than 600 °C (1112 °F).
^ Set Condition: The 02 sensor voltage switches only 11 times or less from rich to lean within 20 seconds during monitoring. Two Trip Fault.

POSSIBLE CAUSES
EXHAUST LEAK
02 SENSOR SIGNAL CIRCUIT
02 SENSOR GROUND CIRCUIT
02 SENSOR

Diagnostic Test
1. CHECK FOR CURRENT DTC





Turn the ignition on.
With the DRB III, read the PCM DTCs.
Is this DTC present?
Yes>> For complete diagnosis of this DTC, (P0137 02 Sensor 2/2 Above Threshold
No>> Go To 2

2. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Note: Check connectors-Clean/repair as necessary. Poor pin to terminal connections can set DTCs. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors specific to this DTC. Wiggle the wires while checking for shorts and open circuits.

Note: Check for any Technical Service Bulletins that may apply.

Were there any problems found?
Yes>> Repair as necessary.
Perform Powertrain Verification Test - Ver 2
No>> The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.