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Longitudinal Dynamics Management




Testing Instructions For Interface Fault In The LDM
An interface fault is stored in the LDM control module (see also test module on the right).

For the LDM function, information from partner control modules is essential. The fault is entered if the relevant partner control module (= interface to the LDM) sends a default value or invalid ID instead of the required information to the LDM and this impairs the LDM function. In this case, a fault memory entry should also be made in the corresponding partner control module.

For this fault, the cause does NOT lie in the LDM control module or in the LDM software!

Possible causes of faults:
- the relevant partner control module is not yet operational
- the sensor system of the relevant partner control module is defective
- general malfunction of the partner control module

Read the fault memory of the relevant partner control module and continue troubleshooting according to test plan in the relevant partner control module. Delete fault code in LDM control module.

If work is currently being carried out on the vehicle and this causes the interface fault in the LDM, under certain circumstances the corresponding fault memory entry can only be made in the partner control module after a terminal change. If necessary, run a terminal change.

If no fault is saved in the relevant partner control module, it can be assumed that there is a sporadic fault. There is no repair measure available for this case: Delete fault code in LDM control module.

Note on clearing the fault memory
Under certain circumstances, the fault in the LDM can only be deleted after a terminal change. In this case, switch the ignition off, wait 10 seconds, switch the ignition on again and then delete the fault.