OBD Guide

U301F

Control Module Wake-up Circuit B Low

U301F is an OBD-II diagnostic trouble code meaning: Control Module Wake-up Circuit B Low. Common causes: wiring harness damage, poor contact in connectors. Estimated repair cost: $17–56.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Problems starting the car
  • Unstable operation of electronic systems
  • Check Engine Light Is On
  • Failure of individual vehicle functions

Causes

  • Wiring harness damage
  • Poor contact in connectors
  • Control module malfunction
  • Short circuit in the circuit

How to Fix

  1. Check the voltage in the wake-up circuit
  2. Inspect the wiring harness for damage
  3. Check and clean connector contacts
  4. Test the control module
  5. Replace damaged components

Related codes

Error U301F by Vehicle Brand

FAQ

What does the U301F code mean?

U301F is an OBD-II diagnostic trouble code that indicates: Control Module Wake-up Circuit B Low

What causes a U301F error code?

The most common causes of U301F include: Wiring harness damage; Poor contact in connectors; Control module malfunction; Short circuit in the circuit.

How do I fix a U301F diagnostic trouble code?

To fix U301F: Check the voltage in the wake-up circuit. Inspect the wiring harness for damage. Check and clean connector contacts. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U301F?

Yes, but get it checked soon

How much does it cost to fix U301F?

The estimated repair cost for U301F is $17–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat