Scania BMU DTC 821 The temperature in the direct current converter E84 (DCC) is too high

BMU Battery Management Unit · Scania · 2 variants

Code 821 (decimal). Some diagnostic tools show it in hexadecimal as 0335.

In short

The direct current converter sensor 1 indicates a temperature above 95°C and/or a temperature above 130°C on sensor 2.

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 821 mean?

What causes Scania DTC 821?

How does the system react?

What are the symptoms?

How to fix Scania BMU fault code 821?

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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 821 in other Scania systems

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