P05F0

Symptoms

• Check Engine Light and/or AdBlue Warning Light Is On
• AdBlue pump does not work normally (excessive noise)
• Excessive consumption of AdBlue reagent
• Possible pump overheating
• Other SCR/AdBlue system codes

Causes

• Welded AdBlue pump power relay contacts
• Short circuit of the supply wire for high voltage
• Generator voltage regulator malfunction
• AdBlue ECU malfunction
• Incorrectly installed power relay (voltage mismatch)

How to Fix

1. Read codes, check on-board voltage (normal: up to 14.5V)
2. Check the AdBlue pump relay for contact welding (measure the voltage at the pump with the ignition off)
3. If voltage is present when the ignition is turned off, the relay is faulty
4. Check the generator: voltage above 15V means the regulator is faulty
5. Inspect the pump wiring for contact with other circuits.
6. Replace relay or eliminate high voltage source

Related codes

Error P05F0 by Vehicle Brand