U0258low severityNetwork

Lost Communication With Auxiliary Heater Control Module

on 2015 Kia Forte 1.8L I4 · FWD

What this code means

The network lost communication with the auxiliary heater control module. The auxiliary or supplemental heater may not operate.

Symptoms

  • Auxiliary heater not working
  • Slow cabin warm-up
  • Heater warning message

Common causes

  • Faulty auxiliary heater control module
  • Wiring or connector fault
  • Power or ground loss
  • Bus communication fault

Diagnostic steps

  1. Scan for stored codes
  2. Check module power and ground
  3. Inspect bus wiring and connectors
  4. Replace heater module if faulty

Other Network codes on this vehicle

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