P05B3

Symptoms

• Check Engine light on
• Possible blown shutter circuit fuse
• Blinds do not respond to control commands
• Other electrical faults in adjacent circuits
• The smell of burning insulation (with a significant short circuit)

Causes

• Short circuit of the control wire to power supply positive (contact with 12 V wiring)
• Internal short circuit in the windings of the blinds actuator
• Damage to the harness wiring insulation (chafing against sharp edges)
• Moisture entering the connector causing the contacts to close
• ECU output stage malfunction

How to Fix

1. Read all codes and check if there are parallel codes on other circuits
2. Disconnect the actuator connector and measure the voltage on the control wire (with the ignition on, the ECU does not activate - it should be ~0 V)
3. Check the insulation of the harness along its entire length - especially where it passes through metal panels
4. Measure the resistance of the control wire to the power positive (should be infinite)
5. Eliminate short circuit: replace the wiring section or isolate the damaged section
6. Check the integrity of the ECU and fuses

Related codes

Error P05B3 by Vehicle Brand