LI54.10-P-071499

Xentry Battery Tester results disagree with workshop assessment
Topic number
LI54.10-P-071499
Version
2
Function group
54.10 - Battery, power supply, voltage converter
Date
3/31/22
Validity
118, 177, 247, 167, 205, 213, 217, 222, 238, 253, 257,
206, 223, 232, 243, 247, 295, 297, 463 except code U98
(LITHIUM-IONEN-STARTERBATTERIE (LISB))
Reason for change
updating model validity
Complaint
The result from the XENTRY battery test does not match the current state of the battery.
Cause
The XENTRY battery tester uses the stored on-board electrical system data in the SAM module to access the health
of the 12 volt battery. The XENTRY battery test may not take into account a single discharge event because the SAM
cannot record the data if the battery is discharged.
Note: A discharged battery does not necessarily need to be replaced. A discharged battery may be recovered with no
permanent damage.
Remedy
1) If the battery is discharged, charge battery. Review WS54.00-P-0037B for minimum charger specifications.
Note the amperage difference between trickle (maintainer) chargers of at least 16A and quick chargers of at least
30A.
Review AP54.10-P-5449U. Note when battery is sufficiently charged the charger current is less 5A.
2) While charging the battery analyze the vehicle data to determine root cause of discharge using the following data
points:
A) Review FSAM on-board electrical data conspicuous records
NOTE: For guidance on use of the on-board electrical data please review the AKUBIS video titled "New on-board
electrical system diagnosis shown on BR 166". The video can be accessed through WIS by following the path WSM-> content by model series --> passenger cars --> ML-Class --> Model 166 --> group 54 --> New on-board electrical
system diagnosis.
B) Customer description
C) Midtronics test
Determine if root cause is due:
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• vehicle technical issue?
• customer behavior?
3) If battery still does not accept charge, create a PTSS case.
Must include with case:
A) Amperage setting of charger and time battery was on charger
B) Xentry Battery Tester results
C) Voltage of battery taken with multimeter: Do not connect charger while taking measurements
D) SAM control unit log
E) Midtronics tester results
F) Workshop analysis of conspicuous SAM data
G) Root cause analysis for battery discharge based on the above documents (technical, customer, etc.)
NOTE: For expedited results when creating a case write customer complaint as "Xentry Battery Tester implausible".
Symptoms
Overall vehicle > Power supply > Battery/On-board electrical system > Battery function > Battery discharges
Operation numbers/damage codes
Op. no.
Operation text
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© Copyright Mercedes-Benz AG
Time
RUTHERE
Damage
code
Note
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