P05F1

Symptoms

• AdBlue pump runs when ignition is off
• Fast consumption of AdBlue reagent
• Check Engine Light and AdBlue Warning Light On
• Possible pump overheating
• Battery discharge when parked for a long time

Causes

• Welded AdBlue pump relay contacts
• Malfunction of the control transistor in the AdBlue control unit
• Relay control circuit short circuit
• AdBlue ECU malfunction

How to Fix

1. Check if the AdBlue pump works with the ignition off (by hand or by ear)
2. Find and remove the AdBlue pump power relay - if the pump stalls, the relay is welded
3. Measure the relay contacts with a multimeter with the relay removed
4. Replace the AdBlue pump power relay
5. If after replacing the relay the error repeats, check the relay control circuit
6. Diagnose the AdBlue system control unit

Related codes

Error P05F1 by Vehicle Brand