E39 / U0073 00
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Malfunction Indicator Lamp
Engine does not start.
Message in SID regarding TCM and TCS/ESP.
All values in MIU are frozen.
No communication with the engine management system.
Cruise control not working.
ECM was Missing on Bus
Fault symptom
Malfunction Indicator Lamp
Engine does not start.
Message in SID regarding TCM and TCS/ESP.
All values in MIU are frozen.
No communication with the engine management system.
Cruise control not working.
On-board diagnosis
Type of diagnosis:
Enable criteria:
| Battery voltage must be between 10 - 18 V. |
Fault criteria:
Dependent:
System reaction to a fault:
| The control module deactivates the output to the A/C relay. |
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 on bus leads or in the component. |
| In order to read DTCs from ECM, communication with CIM is required. If the DTC is stored and read with the diagnostic tool, it indicates an intermittent bus lead fault. |
Functions in the diagnostic tool related to the fault:
| • | Read / Reset Bus Configuration |
| • | Read / Clear Bus Off Counter |
