Replacing Instrument Cluster Electronics (IKE)

The four cases described in the following show under which circumstances which steps must be taken to ensure correct replacement of the instrument cluster electronics (IKE).
These four cases also apply to the integrated version of the instrument cluster phased-in as from 5/97. In this case, the instrument cluster can only be replaced.
Case 1: The control unit for the instrument cluster electronics (IKE) is defective and the light check module control unit (LCM) is OK.

Measures
Result
Remarks
Replace IKE (new part)
The manipulation point is set with the ignition switched on.
The manipulation point is set since the vehicle identification number in the light check module differs from the vehicle identification number in the instrument cluster.
Recode IKE

Code IKE with the central coding code
Code vehicle identification number into IKE

As long as the vehicle identification number is not coded in the instrument cluster electronics (IKE), total odometer recording (only trip recorder recording) does not take place either in the IKE or in the LCM. It should be noted that in the case of an instrument cluster with CAN bus (instrument cluster-integrated version phased-in as from 5/97) AND dynamic stability control (DSC as from 9/97) the DSC is inactive due to the non-matching vehicle identification number. The fault code memory in the DSC control unit should be cleared on completion of this work.
Switch off ignition and switch on again
The manipulation point goes out, the IKE adopts the total odometer reading (mileage) from the LCM and the SIA data.
The data exchange between the IKE control unit and LCM control unit for mutual data storage (SIA data, total odometer reading, vehicle identification number etc.) is now OK. again.

Case 2: The control unit for the instrument cluster electronics (IKE) is OK and the light check module control unit (LCM) is defective.

Measures
Result
Remarks
Replace LCM (new part)
The manipulation point is set with the ignition switched on.
The manipulation point is set since the vehicle identification number in the light check module differs from the vehicle identification number in the instrument cluster.
Recode LCM

Encode LCM with the central encoding code
Code vehicle identification number in the LCM

As long as the vehicle identification number is not coded in the LCM, the total odometer reading will not be recorded in the LCM.
Switch off ignition and switch on again
The manipulation point goes out, the LCM adopts the total odometer reading (mileage) from the IKE and the SIA data.
The data exchange between the IKE control unit and LCM control unit for mutual data storage (SIA data, total odometer reading, vehicle identification number etc.) is now OK. again.

Case 3: The control unit for the instrument cluster electronics (IKE) and the light check module control unit (LCM) must be replaced.

Only replace both control units at the same time if this is unavoidable (stored total odometer reading is irretrievably lost).
Note
Disconnect battery!
Measures
Result
Remarks
Replace IKE and LCM with battery disconnected (new parts)
The manipulation point is set with the ignition switched on and the total odometer reading (mileage) is set to zero.
The previous total odometer reading (mileage) is irretrievably lost.
Code IKE and LCM

Code IKE and LCM in accordance with the central coding code
Code vehicle identification number in IKE and in LCM

As long as the vehicle identification number is not coded, the total odometer reading is not recorded in the IKE and in the LCM. It should be noted that in the case of an instrument cluster with CAN bus (instrument cluster-integrated version phased-in as from 5/97) AND dynamic stability control (DSC as from 9/97) the DSC is inactive due to the non-matching vehicle identification number. The fault code memory in the DSC control unit should be cleared on completion of this work.
Switch off ignition and switch on again
The manipulation point goes out, the LCM adopts the total odometer reading (mileage) from the IKE and the SIA data.
The data exchange between the IKE and LCM for mutual data storage (SIA data, total odometer reading, vehicle identification number etc.) is now OK again.

Case 4: As a check, replace the control unit for the instrument cluster electronics (IKE) or the light check module control unit (LCM).

Note
Although exchanging one of the two control units is possible in principle, it should be avoided wherever possible.
Measures
Result
Remarks
An IKE or LCM control unit from another vehicle is installed as a check.
The manipulation point is set with the ignition switched on and the IKE continues to record the total odometer reading (mileage).
For as long as the vehicle identification number differs, the total odometer reading is only recorded in the IKE. There is no total odometer reading harmonization with the light check module (LCM). It should be noted that in the case of an instrument cluster with CAN bus (instrument cluster-integrated version phased-in as from 5/97) AND dynamic stability control (DSC as from 9/97) the DSC is inactive due to the non-matching vehicle identification number. The fault code memory in the DSC control unit should be cleared on completion of this work.