LI8220P073452

Model Series 223: Ambient Light Warning Assistance Inoperative Message in Cluster
Topic number
LI82.20-P-073452
Version
1
Function group
82.20 - Interior lights
Date
8/9/21
Validity
Model series 223 with code 878
Reason for change
Complaint
The "Ambient Light Warning Assistance Inoperative" warning message is displayed in the instrument cluster and/or
the light-emitting diode strips are not working.
This message is set by the active ambient lighting control unit (N162/1) when a light-emitting diode strip is missing or
where a fault is detected in the light-emitting diode strip.
Cause
The following causes are possible:
1. Rework in active ambient lighting area. The ambient lighting is switched on and the connectors are disconnected
from the wiring harness.NO fault code is stored.
2. Fault code 123X87 (communication error) is stored in the active ambient lighting control unit (N162/1) and the lightemitting diode strip (E34/1-6) is displayed in the quick test with ! (exclamation mark)..
3. Fault code 186X00 (malfunction) stored in the light-emitting diode strips (E34/1-6).
4. Fault code 186x98 (overtemperature) stored in light-emitting diode strips (E34/1-6).
5. There are no fault codes stored in the active ambient lighting control unit (N162/1) and in the light-emitting diode
strips (E34/1-6).
Remedy
1. Lock and unlock vehicle to reset the active ambient lighting control unit (N162/1).
IMPORTANT: When locking, the visual locking verification signal must be visible. Make sure that all the doors are
shut. After locking, wait until the instrument cluster switches to OFF, then press unlock.
2. Run guided test as per XENTRY Diagnosis (check electric lines and connectors). If no faults are found in the
electrical check, please conduct the following:
If fault is in light-emitting diode strip E34/4 -> Replace the light-emitting diode strip.
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© Copyright Mercedes-Benz AG
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If the fault is in light-emitting diode strips E34/1, E34/2, E34/3, E34/5 and E34/6 -> Please create a PTSS case.
3.-5. Update software of light-emitting diode strips (E34/1-6) and active ambient lighting control unit (N162/1):
1.
2.
3.
Update software for each of the light-emitting diode strips (E34/1-6) -> the update must be performed individually
for each light-emitting diode strip.
Update software for active ambient lighting control unit (N162/1). If the latest software is not available, perform
SCN coding (IMPORTANT: Do not run until after the software update for the light-emitting diode strips).
Perform remedy point 1 (lock and unlock vehicle) as described.
6. If points 1. - 3. do not provide a remedy, create a PTSS case.
Symptoms
Lighting > Interior illumination > Ambiance illumination > Does not go on
Operation numbers/damage codes
Op. no.
Operation text
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© Copyright Mercedes-Benz AG
Time
JKANTAR
Damage
code
Note
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