OBD Guide

U0309

Software Incompatibility With Alternative Fuel Control Module

U0309 is an OBD-II diagnostic trouble code meaning: Software Incompatibility With Alternative Fuel Control Module. Common causes: incompatible software update, alternate fuel control module problems. Estimated repair cost: ~$56.

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

Symptoms

  • Check Engine light comes on
  • Reduced engine power
  • Unstable engine operation
  • Switching to emergency mode
  • Problems with switching between fuel types

Causes

  • Incompatible software update
  • Alternate Fuel Control Module Problems
  • Engine ECU malfunction
  • Damage to the wiring harness between modules
  • Incorrect system calibration

How to Fix

  1. Check software versions of all related modules
  2. Update or reinstall the software in accordance with the manufacturer's recommendations
  3. Check the integrity of the wiring harness between the modules
  4. Diagnose the alternative fuel control module
  5. Calibrate the system after updating the software

Related codes

Error U0309 by Vehicle Brand

FAQ

What does the U0309 code mean?

U0309 is an OBD-II diagnostic trouble code that indicates: Software Incompatibility With Alternative Fuel Control Module

What causes a U0309 error code?

The most common causes of U0309 include: Incompatible software update; Alternate Fuel Control Module Problems; Engine ECU malfunction; Damage to the wiring harness between modules.

How do I fix a U0309 diagnostic trouble code?

To fix U0309: Check software versions of all related modules. Update or reinstall the software in accordance with the manufacturer's recommendations. Check the integrity of the wiring harness between the modules. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0309?

Yes, but get it checked soon

How much does it cost to fix U0309?

The estimated repair cost for U0309 is ~$56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat