All codes/U301A

U301A

Control Module Wake-up Circuit A/Open

Moderate severity

Open circuit on the wake-up signal line A — module cannot be woken from sleep via this path. 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.

Open circuit on the wake-up signal line A — module cannot be woken from sleep via this path. 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

  • Wake-up wire broken

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

    high

    Typical part cost: $60-440

  • Gateway module routing CAN messages incorrectly

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

    low

    Typical part cost: $60-440

  • See all causes + fix costs

    Create a free Wrenchify account to unlock the rest for U301A.

    Unlock causes

    Free forever · No credit card

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.

Get the full step-by-step diagnosis

Create a free Wrenchify account to unlock the rest for U301A.

Unlock diagnosis

Free forever · No credit card

Related codes

See related trouble codes

Create a free Wrenchify account to unlock the rest for U301A.

Unlock related codes

Free forever · No credit card

Frequently asked questions

What does U301A mean?

U301A means "Control Module Wake-up Circuit A/Open". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U301A?

wake-up wire broken; 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.

Get the full U301A diagnosis for your vehicle

Year, make, model + step-by-step repair help — free plan included.

Diagnose U301A