ME9 / P2251 00
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Malfunction Indicator Lamp
O2S 1 Reference Ground Circuit, Open
Fault symptom
Malfunction Indicator Lamp
On-board diagnosis
Type of diagnosis:
Enable criteria:
Battery voltage should be between 10.7 and 16 Volts. |
Running with even load for at least 30 seconds. |
Voltage across Nernst cell is 1.36 - 1.48 V for more than 5 seconds. |
Fault criteria:
Voltage across the Nernt cell does not change (control module detects this because preheating is constantly on). |
Open circuit on the lead between control module pin A52 and sensor pin 2. |
Checking the wiring harness
Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short-circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force.
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) |