# Service bulletin B120523

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 10242885
- Published by NHTSA: 2023\-10\-01
- Manufacturer's number: B120523
- Manufacturer's date: 2023\-09\-13
- NHTSA component: POWER TRAIN

## NHTSA's summary

The customer states there is a Drivetrain Malfunction message displayed in the instrument cluster. In addition, the following fault memory entries are saved in the CCU \(Combined Charging Unit\): 0317F2 \- High\-voltage system, insulation fault detected: when switch contactors are closed. 0317F1 \- High\-voltage system, insulation resistance below warning threshold: when switch contactors are closed. The fault memory entries \(isolation faults\) can occur both individually and in combination, and must be traced back to the eDrive motor based on the ISTA test procedure. If the ISTA test procedure lists the possible cause of fault as “a metal chip is found behind the brush module” \(between the brush module and the end shield of the electrical machine\), then a repair is required. Refer to service solution no. 20000794435083 in Aftersales Information Research \(AIR\). Follow information in the Procedure section below

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2023/MC-10242885-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2023/MC-10242885-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Transmission and driveline

## Vehicles listed

- 2022 to 2024 BMW I4
- 2023 BMW I7
- 2021 BMW IX
- 2022 to 2023 BMW IX

## Other bulletins for the same vehicles and component

- [B120523](/bulletins/11030059.md), 2026-03-13, Service bulletin: POWER TRAIN. The customer states there is a Drivetrain Malfunction message displayed in the instrument cluster. In addition, the following fault memory entries are saved in the CCU \(Combined Charging Unit\) 0317F2 \- High\-voltage system, insulation fault detected: when switch contactors are closed. 0317F1 \- High\-voltage system, insulation resistance below warning threshold: when switch contactors are closed. The fault memory entries \(isolation faults\) can occur both individually and in combination and must be traced back to the eDrive motor based on the ISTA test procedure. If ISTA test procedure lists possible cause of fault as; A metal chip is found behind the brush module \(between the brush module and the end shield of the electrical machine\). Repair required. Refer to service solution no. 20000794435083 in Aftersales Information Research \(AIR\). Follow information in the Procedure section below.
- [InVeh\-InApp\-Comm](/bulletins/11029009.md), 2026-02-25, Over\-the\-air update: POWER TRAIN. A manufacturing defect in a bearing of the electronic drive unit could result in bearing damage. This is caused by an unusual acoustic signal in the area of the drive unit. The bearing could fail completely at a later stage, which will be displayed to you by means of a red Check Control message. In this case, the driver is asked to call BMW Roadside Assistance.
- [B121425](/bulletins/11025669.md), 2025-11-25, Service campaign: ELECTRICAL SYSTEM; POWER TRAIN. RSU availability. BMW AG is conducting a Service Action on certain Model Year 2025 \- 2026 BMW vehicles that were produced between March 17, 2021 – November 6, 2025. In certain driving situations there can be a loss of traction or wheel slip followed by a throttle or torque requirement that can potentially damage the axle shafts. Damage of the drive shaft can cause it to break.
- [B370124](/bulletins/11005226.md), 2024-07-25, Service bulletin: POWER TRAIN. While driving at low speeds \(15\-40 mph\) on flat road surfaces, a knocking noise from the front axle may beheard during steering wheel movements.
- [B330124](/bulletins/11005225.md), 2024-07-25, Service bulletin: POWER TRAIN. The vehicle will no longer move when put into gear. There may also be loud noise coming from the HEAT\*\(electric drivetrain\)/Rear axles. \*German acronym for Highly integrated electric drivetrain topology\- Hochintegrierte Elektrifizierte Antriebs\-Topologie
- [B120523](/bulletins/10250361.md), 2024-03-02, Service bulletin: POWER TRAIN. The customer states there is a Drivetrain Malfunction message displayed in the instrument cluster. In addition, the following fault memory entries are saved in the CCU \(Combined Charging Unit\) 0317F2 \- High\-voltage system, insulation fault detected: when switch contactors are closed. 0317F1 \- High\-voltage system, insulation resistance below warning threshold: when switch contactors are closed. The fault memory entries \(isolation faults\) can occur both individually and in combination and must be traced back to the eDrive motor based on the ISTA test procedure. If ISTA test procedure lists possible cause of fault as; A metal chip is found behind the brush module \(between the brush module and the end shield of the electrical machine\). Repair required. Refer to service solution no. 20000794435083 in Aftersales Information Research \(AIR\). Follow information in the Procedure section below.
- [MCAS4023](/bulletins/10242967.md), 2023-10-01, Service bulletin: POWER TRAIN:DRIVELINE:DRIVESHAFT. BMW AG has requested the inspection of all dealer stock of the following part number\(s\) listed below to ensure the spacer is conformed to drawing.
- [B612023](/bulletins/10242700.md), 2023-09-25, Service bulletin: ELECTRICAL SYSTEM; POWER TRAIN. ?The customer states there is a Drivetrain Malfunction message displayed in the instrument cluster, and in some cases the vehicle will not go into drive readiness.
- [B120522](/bulletins/10241364.md), 2023-08-28, Service bulletin: POWER TRAIN. BMW AG has issued a Delivery Stop \(effective December 1, 2022\) on certain Model Year 2023 BMW i4 andi7 vehicles that were produced between October 5, 2022 and November 10, 2022. A bearing in the front electric drive unit could fail due to a manufacturing defect, resulting in a noise while driving.
- [B120422](/bulletins/10241363.md), 2023-08-28, Service bulletin: POWER TRAIN. BMW AG has issued a Delivery Stop \(effective December 1, 2022\) on certain Model Year 2023 BMW iX SAV vehicles that were produced between October 5, 2022 and November 10, 2022. A bearing in the front electric drive unit could fail due to a manufacturing defect, resulting in a noise while driving.

JSON: [/v1/bulletins/10242885](/v1/bulletins/10242885)

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