ME9 / P2237 00
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Malfunction Indicator Lamp
O2S 1 Pump Current Circiut, Open
Fault symptom
Malfunction Indicator Lamp
On-board diagnosis
Type of diagnosis:
Enable criteria:
| Battery voltage should be between 10.7 and 16 Volts. |
| Closed loop lambda control active. |
| Sensor in normal operating range (715°C and up). |
| Control module requests lambda more or less than 1. |
| Total air mass consumed - 400 g. |
| NONE of the following DTCs must be detected: |
Fault criteria:
| No change in O2S1 signal for more than 4 seconds. |
| 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:
| • | Short Term Fuel Trim Status |
| (See also description of readings/activations in diagnostic tool) |
