BR117, BR156, BR176, BR242, and BT246 Vehicle does not start, battery discharged.
Topic number

LI54.10-P-066342

Version

2

Design group

54.10 Battery, power supply, voltage converter

Date

07-19-2017

Validity

MFA (BR117/ BR156/ BR176/ BR242/ BT246)

Reason for change

Revised analysis

Reason for block

Complaint:

Vehicle does not start, battery discharged.
The on-board electrical system data indicates a high discharge in the engine-off cycle; "CAN bus awake unusually
long", "Charge balance UNUSUAL".

Cause:

To be able to assess whether a bus keepawake event caused the battery discharge, it is necessary to examine the
stationary cycles. A constantly active CAN is identified by the text "Interior CAN awake unusually long" (see attachment). If this text is not displayed, the battery discharge has a different cause.
Cause 1:
IC (instrument cluster) is keeping the CAN bus awake. Vehicle battery is being discharged.
Affects vehicles with code 807 (Model Year 2017)
.
Fault identification:
1. Affects vehicles as of code 807.
2. The on-board electrical system data indicates a high discharge in the engine-off cycle; "CAN bus awake unusually
long", "Charge balance UNUSUAL".
3. The bus keepawake entry names the IC.
Cause 2:
HERMES is keeping the CAN bus awake, only affects USA (code 494). Refer to LI82.85-P-066086.
Vehicles with code 362 (HERMES LTE communication module), code 522 (Audio 20) and code 807.
NOT Cause 1 or Cause 2:
07-19-2017 2:50 PM
© Copyright Daimler AG

MYNELSO

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Reference Remedy 3 below for more information.

Remedy:

Remedy 1:
DO NOT REPLACE ANY PARTS
Remedy with clean point will be published.
Damage code: 54201-54
Remedy 2:
Refer to LI82.85-P-066086.
Damage code: 8209Z-90
Remedy 3:
If not resolved by Remedy 1 or Remedy 2, please create a PTSS case with all the documents listed below and include
in the case attachments.
Engineering may provide further instruction upon reviewing each case.
Documents needed in case attachments:
1. Quick test
2. Control units event log for signal acquisition and actuation module (SAM)
3. Bus keepawake event detection (from EIS --> Actual values)
3.1. Last bus keepawake entry
3.2. Last-but-one bus keepawake entry
4. Up-to-date quiescent current measurement

Symptoms
Overall vehicle / Power supply / Battery/On-board electrical system / Battery function / Battery discharges
Overall vehicle / Power supply / Battery/On-board electrical system / Battery/on-board electrical system display message / Low voltage Charge battery

Operation numbers/damage codes
Op. no.

Operation text

07-19-2017 2:50 PM
© Copyright Daimler AG

Time

MYNELSO

Damage
code

Note

54201 54

Instrument cluster - no-load current
too high

8209Z 90

Communication module for telematics service - software release

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