Scania EMS DTC 4221 Exhaust gas pressure sensor T125

EMS Engine Management System · Scania · 2 variants

Code 4221 (decimal). Some diagnostic tools show it in hexadecimal as 107D.

In short

The engine control unit indicates too low a voltage in the circuit for the charge air pressure sensor.

Variant 1: Charge air pressure sensor T166, short circuit to low voltage

Applies to: EMS10

What does Scania EMS fault code 4221 mean?

What causes Scania DTC 4221?

How to fix Scania EMS fault code 4221?

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Variant 2

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 4221 in other Scania systems

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