Scania BCI DTC 721 Low voltage, analogue input signal, expansion unit B (pin 20)

BCI BCI control unit · Scania · 2 variants

Code 721 (decimal). Some diagnostic tools show it in hexadecimal as 02D1.

In short

Implausible signal, voltage too low.

Variant 1

Applies to: BCI2 (BWE)

What does Scania BCI fault code 721 mean?

What causes Scania DTC 721?

What are the symptoms?

How to fix Scania BCI fault code 721?

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Variant 2

Applies to: BCI3 (BWE)

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

Code 721 in other Scania systems

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