Code result

U300E

Ignition Input On

Moderate severity

What it means

Fault on the ignition ON input — module does not see ON state when other inputs say ON, or vice versa.

Is it safe to drive?

Use caution

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

  • Ignition switch contacts worn

    high

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

  • Gateway module routing CAN messages incorrectly

    low

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

  • CAN terminating resistor (120 Ω) drifted out of spec

    low

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

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