Scania EMD DTC 4821 Ignition module, timeout

EMD EMD control unit · Scania

Code 4821 (decimal). Some diagnostic tools show it in hexadecimal as 12D5.

In short

The OCS control unit detects a fault and forwards the information to the EMS control unit.

Applies to: EMD1

What does Scania EMD fault code 4821 mean?

What causes Scania DTC 4821?

How does the system react?

How to fix Scania EMD fault code 4821?

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

Code 4821 in other Scania systems

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