Functional impairment of 48 V on-board electrical system
Topic number

LI54.10-P-069698

Version

9

Function group

54.10 Battery, power supply, voltage converter

Date

02-16-2021

Validity

Model series 257, 213, 238, 167, 290 with code B01

Reason for change

Updating remedy 1 to update software for all engines.
Removing cause/remedy 5 for simplicity and due to infrequency.

Reason for block

Complaint:

Various causes are possible. The faults listed in the various causes do not all have to be present at all times. Some of
these complaints may overlap. Rely on the faults listed in the Cause section for identifying the correct Remedy.
1. No start
2. Yellow or red instrument cluster message for 48 V on-board electrical system battery (G1/3)
3. Limp home mode, overheating, A/C not blowing cold, or loss of acceleration

Cause:

Cause 1: Software causes intermittent no starts with fault B183387 in DC/DC converter N83/1
Cause 2: Software causes Permanent no starts with fault B183349 and B183371 in 48V battery G1/3.
Cause 3: Hardware short circuit in 48V system causes fault B183319 in 48V battery
Cause 4: 48V battery detects abnormality and disconnects causing additional symptoms: Limp Home Mode, overheating, A/C not blowing cold, or loss of acceleration This cause will always have fault code in G1/3: B183371 but will Not
have B183349.

Remedy:

Note: each of these remedies correspond to a specific cause. Make sure to match correct Cause with Remedy.
Remedy 1:
Update software in G1/3 (48V battery) using newest Xentry software and AddOns

Remedy 2:
1. Check software version in 48V battery via quick test. If 19/46 000 replace only 48V battery (regardless of other
faults)
02-16-2021 9:08 PM
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2. Update DC/DC converter N83/1 if newer software is available.
3. If software version is Not 19/46 000, open a PTSS case.
Remedy for 3:
1. Disconnect the 48V battery.
2. Remove terminal 40 on 48V battery to DC/DC converter N83/1.
3. Check in Xentry: is error code still present?
If yes, replace 48V on-board power battery G1/3 and settle for damage code 540HY73.
If no, short must be outside the 48 V line battery. Possibly causes are the cables, screw connections, or 48V components.
--Disconnect all 48V components one at a time.
--Check after disconnecting each component if the error code "B183319" is still in the 48V battery G1/3.
--If after disconnected the fault is gone, or the vehicle can be started, the disconnected component is defective and
should be replaced.

PRELIMINARY MEASURES required for Remedy 4
NOTE: It is imperative to document each one of these steps in detail. Some of the remedies will require opening a
PTSS case. This information is vital in helping to expedite the diagnostic process.
• Make sure Add-ons are are up to date in Xentry Machine
• Before clearing faults or road test: pull initial Quick Test and DC/DC CUL.
• Road test to attempt to duplicate fault before proceeding below. Test drive with multiple ECO stop/starts and under as many various driving styles as possible: manual, automatic, slow, aggressive, Comfort, Sport+, etc. SAFETY is
more important than testing. Please proceed with caution.
• Upload all below documentation and perform testing:
• Make sure to indicate in file names or descriptions the order the uploaded documents occurred.
• Quick Test and DC/DC Control Unit log (after test drive)
• Complete all guided test(s) and subsequent physical layer inspection.
• Detach line between DC/DC converter N83/1 and 48 V on-board electrical system battery. Check for: damage, soiling, corrosion,and check resistance of all cable pins (should