ME9 / P2239 00

Read the instructions below then start the fault diagnostic procedure.

Symptom: Malfunction Indicator Lamp

P2239 00

Fault symptom

Malfunction Indicator Lamp

On-board diagnosis

Type of diagnosis:

Continuous

Enable criteria:

Battery voltage should be between 10.7 and 16 Volts.

Closed loop lambda control active.

Voltage across the Nernst cell is 1.4902 - 1.509 V.

Running with even load.

Fault criteria:

Current lambda deviates 2.5% from requested value.

Open circuit on the lead between control module pin A3 and sensor pin 1.

Checking the wiring harness

Jiggle the wiring harness at several points to detect intermittent breaks or short circuits. Check also the connector for oxidation or loose pins.

Diagnostic help

Diagnosis regards:

Electrical fault in connecting leads or component.

Functions in the diagnostic tool related to the fault:

Test value:

•	Requested O2S1 Lambda

•	O2S1 lambda

•	O2S1 Pump Current

•	O2S 1 Preheating

•	Short Term Fuel Trim Status

•	Closed Loop

•	Total Fuel Trim

(See also description of readings/activations in diagnostic tool)