All codes/U0243

U0243

Lost Communication With Parking Assist Control Module B

Moderate severity

ECU lost communication with parking assist control module B (additional ultrasonic/visual parking system).

ECU lost communication with parking assist control module B (additional ultrasonic/visual parking system).

Common causes

  • Module unpowered

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

    high

    Typical part cost: $130-1650

  • Gateway module routing CAN messages incorrectly

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

    low

    Typical part cost: $130-1650

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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 U0243 mean?

U0243 means "Lost Communication With Parking Assist Control Module B". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U0243?

module unpowered; 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?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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