Scania APS DTC 129 Voltage supply

APS Air Processing System · Scania

Code 129 (decimal). Some diagnostic tools show it in hexadecimal as 0081.

In short

The supply voltage to the control unit has dropped below 20 volts.

Applies to: APS1

What does Scania APS fault code 129 mean?

What causes Scania DTC 129?

How does the system react?

How to fix Scania APS fault code 129?

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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.