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P0135

Read the instructions below then start the fault diagnostic procedure.

Symptom: CHECK ENGINE lamp on.

P0135


Heating, Front Heated Oxygen Sensor Circuit. Current outside limits.


Fault symptoms

CHECK ENGINE lamp on.

Conditions




• Preheating active

• Preheating current below 500 mA or above 2300 mA for 5 sec.


Diagnostic help

The oxygen sensor preheating current can be read with the diagnostic tool.


- Select " Data Display / Output Control (New)".



- Select " Preheating O2S 1."


the diagnostic tool should show the actual preheating current of 700 - 1000 mA with warm engine. The oxygen sensor preheating can be activated with the diagnostic tool. Note that only the control module output is grounded during activation, the sensor will not heat up as the main relay has not operated. A diagnostic code will also be generated irrespective of whether the sensor is connected or not. The diagnostic code must be cleared after fault diagnosis has been completed.


- Select " Data Display / Output Control (New)".



- Select " Preheating O2S 1".


If diagnostic trouble codes P0135 and P0141 are present, the fault is caused by:

• fuse 38 blown

• the lead between H33-4 pin 8 and crimp J76.

Checking the wiring harness. Intermittent faults may occur in connection with short circuits and open circuits. Jiggle the wiring harness at several points and in several directions to locate any problems in the wiring, including intermediate connectors. Observe the multimeter, scan tool or test lamp during the check.