Scania EMS DTC 4521 Relay to injectors R651

EMS Engine Management System · Scania · 3 variants

Code 4521 (decimal). Some diagnostic tools show it in hexadecimal as 11A9.

In short

The engine control unit indicates a short circuit to voltage supply.

Variant 1: Injector cylinder 5, short circuit to voltage supply

Applies to: EMS10

What does Scania EMS fault code 4521 mean?

What are the symptoms?

How to fix Scania EMS fault code 4521?

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Variant 2

Applies to: EMS S7

Variant 3

Applies to: EMS S8

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

Code 4521 in other Scania systems