BMU 640 Scania Isolation measurement could not be performed

BMU Battery Management Unit · Scania · 2 variants

Code 640 (decimal). Some diagnostic tools show it in hexadecimal as 0280.

In short

The BMU control unit failed to detect the insulation signal.

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 640 mean?

What causes Scania DTC 640?

How does the system react?

How to fix Scania BMU fault code 640?

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Variant 2

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 640 in other Scania systems

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