Scania BMU DTC 843 Fan M40 for cooling MGS and DCC, overload

BMU Battery Management Unit · Scania · 2 variants

Code 843 (decimal). Some diagnostic tools show it in hexadecimal as 034B.

In short

Electrical fault in fan M40.

Variant 1

Applies to: BMU6 (RES)BMU6 (RESXA)BMU6 (RESXB)BMU6 (RESXC)BMU6 (RESXD)BMU6 (RESXE)BMU6 (RESXF)BMU6 (RESXG)BMU6 (RESXH)BMU6 (RESXI)BMU6 (RESXJ)BMU6 (RESXK)

What does Scania BMU fault code 843 mean?

What causes Scania DTC 843?

What are the symptoms?

How to fix Scania BMU fault code 843?

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Variant 2: Fan M40 for rechargeable energy storage system

Applies to: BMU5

This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.

Code 843 in other Scania systems

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