OBD Guide

U103C

Keyless Ignition Node Communication

U103C is an OBD-II diagnostic trouble code meaning: Keyless Ignition Node Communication. Common causes: malfunction of the keyless start unit, damage to the wiring harness to the assembly. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • The car does not respond to the key fob
  • Can't start engine with button
  • The immobilizer indicator is flashing
  • Error message on the dashboard
  • Intermittent operation of the keyless system

Causes

  • Malfunction of the keyless start unit
  • Damage to the wiring harness to the assembly
  • Node power problems
  • Interference on the CAN bus
  • Keyless system antenna malfunction

How to Fix

  1. Check fuses associated with the system
  2. Diagnose the condition of the wiring harness
  3. Check the power supply to the keyless start unit
  4. Scan the CAN bus for errors
  5. Test or replace the keyless start assembly

Related codes

FAQ

What does the U103C code mean?

U103C is an OBD-II diagnostic trouble code that indicates: Keyless Ignition Node Communication

What causes a U103C error code?

The most common causes of U103C include: Malfunction of the keyless start unit; Damage to the wiring harness to the assembly; Node power problems; Interference on the CAN bus.

How do I fix a U103C diagnostic trouble code?

To fix U103C: Check fuses associated with the system. Diagnose the condition of the wiring harness. Check the power supply to the keyless start unit. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U103C?

Yes, but get it checked soon

How much does it cost to fix U103C?

The estimated repair cost for U103C is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat