Scania BMU DTC 631 Fault in pre-charging of the contactor unit

BMU Battery Management Unit · Scania

Code 631 (decimal). Some diagnostic tools show it in hexadecimal as 0277.

In short

Timeout because the time for pre-charging is above 1 s.

Applies to: BMU5BMU6 (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 631 mean?

What causes Scania DTC 631?

How does the system react?

How to fix Scania BMU fault code 631?

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

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