E39 / P0102 00
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Malfunction Indicator Lamp
Performance loss.
Mass Air Flow Sensor Circuit Low Input
Fault symptom
Malfunction Indicator Lamp
Performance loss.
On-board diagnosis
Type of diagnosis:
Enable criteria:
| Battery voltage must be between 10 - 18 V. |
Fault criteria:
| When the signal from the mass air flow sensor is below 0.92 g/s. |
System reaction to a fault:
| Limp home - Only basic charge pressure |
Fault handling:
| (See section Fault handling III, "Other emission-related components and functions" for more information.) |
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:
| • | Requested Throttle Position |
| (See also description of readings/activations in diagnostic tool) |
