All codes/U3528

U3528

High Voltage System Interlock Circuit G High

High severity

HVIL loop G voltage above expected range. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.

HVIL loop G voltage above expected range. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.

Common causes

  • Interlock loop open

    One of the most commonly reported causes for this code — check this first.

    high

    Typical part cost: $110-1650

  • Gateway module routing CAN messages incorrectly

    Less common, but worth ruling out after the more likely causes.

    low

    Typical part cost: $110-1650

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First things to check

  1. 1Confirm the code with a scan tool and check for additional related codes.
  2. 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does U3528 mean?

U3528 means "High Voltage System Interlock Circuit G High". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U3528?

interlock loop open; gateway module routing can messages incorrectly; can terminating resistor (120 ω) drifted out of spec — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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