BMU 777 Scania Incorrect behaviour of the coolant pump in the direct current converter E84 (DCC) and inverter E82 (MGU) cooling system

BMU Battery Management Unit · Scania · 2 variants

Code 777 (decimal). Some diagnostic tools show it in hexadecimal as 0309.

In short

The coolant pump of the direct current converter and inverter cooling system does not respond correctly to a request.

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 777 mean?

What causes Scania DTC 777?

How does the system react?

What are the symptoms?

How to fix Scania BMU fault code 777?

Read the full explanation with Premium

Causes, system reaction, symptoms and step-by-step repair instructions for every fault code are available to Premium members.

  • Full explanations of every code and brand
  • Causes, symptoms and repair steps
  • New brands and codes included
Get Premium – 7,50 € / month I already have an account

Yearly plan: pay 10 months, get 12. Cancel at any time.

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 777 in other Scania systems

Compare code 777 in every system →