Scania AMS DTC 8389 Electrically heated reductant hose H25, open circuit or short circuit to supply voltage

AMS AMS control unit · Scania · 2 variants

Code 8389 (decimal). Some diagnostic tools show it in hexadecimal as 20C5.

In short

The control unit for the exhaust gas aftertreatment management system indicates that the pins for the electrically heated reductant hose are short circuited to supply voltage or there is an open circuit.

Variant 1

Applies to: AMS1

What does Scania AMS fault code 8389 mean?

What causes Scania DTC 8389?

How does the system react?

How to fix Scania AMS fault code 8389?

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Variant 2

Applies to: AMS2

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

Code 8389 in other Scania systems