O2 Sensor 1/1 Heater Circuit Open

P0135 - O2 SENSOR 1/1 HEATER CIRCUIT OPEN





When Monitored and Set Condition

- When Monitored: Engine Running and Heater duty cycle greater than 0%.
- Set Condition: O2 Heater Temperature does not reach 575° C (959° F) within 90 seconds during monitoring conditions. Two Trip Fault.







Diagnostic Test

1. CHECK FOR CURRENT DTC





Turn the ignition on.

With the DRB III(R), read PCM DTCs.

Is this DTC present?

Yes

- For complete diagnosis of this DTC, refer to (P0135) O2 SENSOR 1/1 HEATER CIRCUIT HIGH

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. 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.