Instrument cluster display (driver's side) intermittently remains dark
Topic number

LI54.30-P-069821

Version

4

Function group

54.30 Instrument cluster, display instruments, hazard
warning device

Date

05-21-2020

Validity

Model series 118, 177, 247 with code 859

Reason for change

Description of remedy changed

Reason for block

Complaint:

The display on the driver's side (instrument cluster) may remain dark upon opening the door and the welcome animation is not shown. The display may continue to remain dark after the engine is started.
NOTE: This document is only relevant to the above complaint. This complaint is not known to occur while the vehicle
is in motion.

Cause:

- Instrument cluster control unit (N133/1) software
- Display (A40/16) software
- Damage to HSVL lines, shielding, or connectors
- Display (A40/16) hardware

Remedy:

Ensure software for both the instrument cluster control unit (N133/1) and the display cluster (A40/16) are up-to-date
NOTE: Check whether any relevant DTCs are active or stored in the XENTRY quick test, and process these accordingly using XENTRY diagnosis before proceeding with the below steps.
Inspect the HSVL lines (and shielding) between N133/1 and A40/16. Proceed as follows to check the quality of the
connections at the display:
- Remove the display from the dashboard leaving connections intact.
- With the display active, manipulate the HSVL lines and connectors and observe the the display for any loss of video
signal.
- IF movement reproduces the problem, then check the seating/fit of the connector for both video lines on the display
(A40/16).
- IF the connector is seated properly, replace the video lines. Ensure the lines are routed properly when re-installing
the display.
05-21-2020 3:40 PM
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- IF the complaint re-occurs after installation of the new video lines then proceed with replacement of the display
(A40/16).
If after the above measures are taken and the complaint still occurs please open a PTSS case with the following information:
- Initial quick test
- Instrument cluster (N133/1) control unit log
- Display cluster (A40/16) control unit log

Symptoms
Communication/information / Information display / Displays / Multifunction display / Multifunction display, menu / Not
operable
Communication/information / Information display / Overall component / Instrument cluster, total failure / Malfunction

Control unit/fault code
Control unit

Fault code

Fault text

A40/16 - Display cluster 'Instrument cluster and head
unit' (ZAN) (DISP6) (A (177),
CLA (118))

-

-

Operation numbers/damage codes
Op. no.

Operation text

Time

Damage
code

Note

540SU 73

05-21-2020 3:40 PM
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