B0939

Symptoms

• False coolant level readings on the dashboard
• Check engine light is on
• The engine may go into emergency mode
• Incorrect operation of the cooling system

Causes

• Coolant level sensor malfunction
• Short circuit in wiring harness
• Broken or damaged wires
• Problems with the ECU
• Corrosion of sensor contacts or connectors

How to Fix

1. Check the coolant level and add if necessary
2. Inspect the coolant level sensor for damage
3. Check the wiring harness and connectors for damage or corrosion.
4. Test the sensor with a multimeter
5. Replace the sensor if a fault is detected
6. Clean or replace connectors if necessary
7. Check the ECU for errors

Related codes

Error B0939 by Vehicle Brand