Functional Impairment of 48 V On-board Electrical System
Topic number

LI54.10-P-069698

Version

18

Function group

54.10 - Battery, power supply, voltage converter

Date

12/12/22

Validity

Model series 167, 257, 213, 238, 290 with code B01
Does Not apply to 223 or 206.

Reason for change

SW available for MY21 vehicles with M256 engine.

Complaint
This LI does Not apply to 223 or 206 which use a different generation of 48V systems. Please follow the relevant guided tests for the 223 and 206.
For 223 with fault code B1FCB97 follow LI54.10-P-073164.
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
4. Check Engine Light

Cause
Cause 1: Software causes Intermittent No Starts with fault B183387 in DC/DC converter N83/1
Cause 2: Software causes Permanent No Start with fault B183349. May also have fault B183371.
Cause 3: Hardware short circuit in 48V system causes fault B183319 in 48V battery. May also have fault B183371.
Cause 4: Internal 48V battery Peltier cooling element failure causes fault B183397
Cause 5: This will Always have fault code B183371 but different from cause 2 and 3 -- it will Not have B183349,
B183319, or any other faults in the 48V battery. This will only have fault B183371 in 48V battery. Cause 5 is from the
48V battery detecting an abnormality which then causes the 48V battery to disconnect itself. The disconnected 48V
battery then causes subsequent symptoms: Limp Home Mode, overheating, A/C not blowing cold, or loss of acceleration
Cause 6: Check Engine Light with fault P0606F1 in the N127 PTCU

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Remedy
Note: each of these remedies correspond to a specific cause. Make sure to match correct Cause with Remedy.
Remedy 1:

1.
2.

Update software in G1/3 (48V battery) using newest Xentry software and Add-ons
Road test and release vehicle if no further symptoms

Remedy 2:

1.
2.
3.
4.
5.
6.
7.
8.

Xentry MUST be connected with VCI cable to correctly complete this remedy.
Complete guided test for B183349.
If guided test completes, vehicle starts, and drive cycles show no further symptoms, release vehicle.
If after guided test completes, Xentry states to replace 48V battery: replace only 48V battery. If vehicle is a
MY21 w/M256 engine, update SW in 48V battery
If this is a repeat visit for fault B183349 and guided test has already been completed, open a TIPS case.
If guided test does not complete OR symptoms are still present open a TIPS case.
If communication cannot be established with 48V battery perform physical layer check at 12V wiring to DCDC. If
no abnormalities found, replace the 48V battery.
If guided test completes but a new fault code is present (such as B183319, B183371, etc.) follow the relevant
Cause/Remedy for that fault in this LI.

Remedy for 3:
1. If fault is not Current (only Stored):

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

Perform Xentry actuations for all 48V components.
Create a TIPS case with ALL Preliminary measures required as noted below for Remedy 5
Upload to TIPS case ISA performance data from the N129.
ISA performance data location in XD:
N129 control unit under Special Procedures
"Procedures for support queries to market support"
"Collation of diagnosis performance data"
"engine at idle"
After next screen loads with data click continue. The next screen will show where the .CSV file is located in your
Xentry. Navigate to this location in XD and upload this CSV file to the case.
Note it is important this is a .CSV file extension and Not a screenshot or print of the data values.

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2. If fault is Current AND Stored:
A) Disconnect the 48V battery.
B) Remove terminal 40 on 48V battery to DC/DC converter N83/1.
C) Check Xentry: is error code Current, Stored, and not erasable?
--If yes, replace 48V on-board power battery G1/3 and set damage code 540HY73.
If no, short circuit must be somewhere other than the 48V battery. Possible causes: cables, screw connections, or
48V components.
To Troubleshoot:
--Disconnect each 48V components one at a time at 48V prefuse box.
--Check after disconnecting that component if the error code "B183319" is still in the 48V battery G1/3.
--If after disconnecting the fault goes from Current to Stored, or the vehicle can be started, then that current disconnected component is defective and should be replaced.
--If unable to reproduce or cannot clear faults open TIPS case.

Remedy 4:
1. Order and replace only 48V battery.

Remedy 5:
All MY21 vehicles with M256 engine:

1.
2.
3.
4.
5.
6.

Update software in G1/3 (48V battery) using newest Xentry software and Add-ons
Road test and release vehicle if no further symptoms
If any abnormalities or this is a return visit after SW update was performed, open a TIPS case with the following:
Initial quick test
DCDC CUL
Time and date of occurrence

All other vehicles:
1. Perform below physical layer check for correct model inspections looking for corrosion, abnormalities, etc.
If nothing is found release to the customer.
--Check the connection at W244/1 (Bus Bar)
--Check for 48V terminal 40/41 connections with following instructions
--Check each screw connection:
--Can the cable lug be moved? Is it wobbling? Are deformations on the cable lug? Are there discolorations or signs of
overheating visible? Are paint residues or dirt visible on the bolt or cable lug?
--There are two types of ground bolts M6 and M8:
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--For M6 bolts with paint-scraping nut, the thread cuts into the paint and the current flows through the nut and the thread
into the bolts. No further contact surface on the bolt is required!
--If one of these is suspected of causing a contacting problem: create a TIPS case.
--For M8 ground points, the current flows through the contact surface between the bolt foot and the cable lug. For these,
ensure this surface is clean and not painted. If painted remove paint.
Model: 167
-W106/1 (circuit 41 on battery)
-F153/2 (Pre-fuse box engine compartment to DC/DC converter terminal 40)
-F150/2 A2 (Pre-fuse box battery circuit 30)
Model: 213, 238, 257, 290
-F153/2 (Pre-fuse box engine compartment circuit 40)
-Powerpack 48V (circuit 30 and 31)
-W106/2 (battery grounds)
-W106/3
-N129 (ISA circuit 40 and 41)
-W30/11
Last inspect 48V cables and control unit connectors for the following
-Is the plug firmly locked?
-Are the contact pins in the plug locked?
-Are there signs of mechanical damage to the plug or pins (e.g. due to improper repair attempts, etc.)
-Are there traces of water, corrosion or traces of thermal overload?
-Check lines for damage such as abrasion, animal bites or other types of damage.
-Check all 48V screw and plug connections on each component present in the vehicle:
-Circuit 40/41 cables on components:
---Document release torque of circuit 40/41 M8 bolts and retorque to 16N-m
If after reviewing the above nothing is found the vehicle can be released to the customer.
If any abnormalities or this is a return visit, open a TIPS case with preliminary documentation requested.

Remedy 6:
If fault P0606F1 is Active and Stored in the N127 PTCU and cannot be cleared, replace the 48V battery only, clear all
faults, and road test.
---If the CEL does not return, vehicle can be released.
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---If CEL returns or other symptoms are still present, open a TIPS case.

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 > Battery/Alternator - Serviced Required

Control unit/fault code
Control unit

Fault text

N83/1 - DC/DC converter (DDW) (DCDC48_222)

B183301 - The battery for the 48V on-board electrical
system has a malfunction. There is a general electrical
fault. (LIB48_222)
B183214 - The 48V on-board electrical system has a malfunction. There is a short circuit to ground or an open circuit. (LIB48_222)
B183216 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has not been attained. (LIB48_222)
B183217 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has been
exceeded. (LIB48_222)
B183371 - The battery for the 48V on-board electrical system has a malfunction. The actuator is blocked.
(LIB48_222)
B183319 - The battery for the 48V on-board electrical
system has a malfunction. The limit value for current has
been exceeded. (LIB48_222)

N83/1 - DC/DC converter (DDW) (DCDC48_222)

B183301 - The battery for the 48V on-board electrical
system has a malfunction. There is a general electrical
fault. (LIB48_222)
B183214 - The 48V on-board electrical system has a malfunction. There is a short circuit to ground or an open circuit. (LIB48_222)
B183216 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has not been attained. (LIB48_222)
B183217 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has been
exceeded. (LIB48_222)
B183371 - The battery for the 48V on-board electrical system has a malfunction. The actuator is blocked.
(LIB48_222)
B183319 - The battery for the 48V on-board electrical
system has a malfunction. The limit value for current has
been exceeded. (LIB48_222)

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N83/1 - DC/DC converter (DDW) (DCDC48_222)

B183301 - The battery for the 48V on-board electrical
system has a malfunction. There is a general electrical
fault. (LIB48_222)
B183214 - The 48V on-board electrical system has a malfunction. There is a short circuit to ground or an open circuit. (LIB48_222)
B183216 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has not been attained. (LIB48_222)
B183217 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has been
exceeded. (LIB48_222)
B183371 - The battery for the 48V on-board electrical system has a malfunction. The actuator is blocked.
(LIB48_222)
B183319 - The battery for the 48V on-board electrical
system has a malfunction. The limit value for current has
been exceeded. (LIB48_222)

N83/1 - DC/DC converter (DDW) (DCDC48_222)

B183301 - The battery for the 48V on-board electrical
system has a malfunction. There is a general electrical
fault. (LIB48_222)
B183214 - The 48V on-board electrical system has a malfunction. There is a short circuit to ground or an open circuit. (LIB48_222)
B183216 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has not been attained. (LIB48_222)
B183217 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has been
exceeded. (LIB48_222)
B183371 - The battery for the 48V on-board electrical system has a malfunction. The actuator is blocked.
(LIB48_222)
B183319 - The battery for the 48V on-board electrical
system has a malfunction. The limit value for current has
been exceeded. (LIB48_222)

N83/1 - DC/DC converter (DDW) (DCDC48_222)

B183301 - The battery for the 48V on-board electrical
system has a malfunction. There is a general electrical
fault. (LIB48_222)
B183214 - The 48V on-board electrical system has a malfunction. There is a short circuit to ground or an open circuit. (LIB48_222)
B183216 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has not been attained. (LIB48_222)

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B183217 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has been
exceeded. (LIB48_222)
B183371 - The battery for the 48V on-board electrical system has a malfunction. The actuator is blocked.
(LIB48_222)
B183319 - The battery for the 48V on-board electrical
system has a malfunction. The limit value for current has
been exceeded. (LIB48_222)
N83/1 - DC/DC converter (DDW) (DCDC48_222)

B183301 - The battery for the 48V on-board electrical
system has a malfunction. There is a general electrical
fault. (LIB48_222)
B183214 - The 48V on-board electrical system has a malfunction. There is a short circuit to ground or an open circuit. (LIB48_222)
B183216 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has not been attained. (LIB48_222)
B183217 - The 48V on-board electrical system has a malfunction. The limit value for electrical voltage has been
exceeded. (LIB48_222)
B183371 - The battery for the 48V on-board electrical system has a malfunction. The actuator is blocked.
(LIB48_222)
B183319 - The battery for the 48V on-board electrical
system has a malfunction. The limit value for current has
been exceeded. (LIB48_222)

Operation numbers/damage codes
Op. no.

Operation text

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Time

WINTJAC

Damage
code

Note

540HY73

Battery 48 V on-board electrical system - electrical fault

5416D73

DC/DC converter 48 V on-board
electrical system

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