U3540

High Voltage System Interlock Circuit N High

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$56–278 (est.)

Symptoms

Check Engine light comes on
Engine power limitation
Inability to start the high voltage system
Error message on the dashboard
The car goes into emergency mode

Causes

Open or short circuit in the interlock circuit
Damaged high voltage system connectors
Lock relay fault
Problems with high voltage battery
High voltage system controller malfunction

How to Fix

Check the integrity of all wires in the interlock circuit
Inspect and clean all high voltage system connectors
Check the functionality of the blocking relay
Test high voltage battery
Diagnostics and possible replacement of the high-voltage system controller
Repair only from an authorized dealer

Related codes

U3400 U3541 U3550