P0030low severityPowertrain

HO2S Heater Control Circuit Bank 1 Sensor 1

on 2015 Kia Forte 1.8L I4 · FWD

What this code means

The PCM detected a malfunction in the heater circuit of the upstream heated oxygen sensor (Bank 1, Sensor 1).

Symptoms

  • Check Engine Light
  • Poor fuel economy
  • Longer warmup emissions
  • Failed emissions test

Common causes

  • Faulty O2 sensor heater
  • Blown fuse
  • Wiring issue
  • PCM heater driver failure

Diagnostic steps

  1. Check O2 sensor heater fuse
  2. Test heater circuit resistance (should be 2-30 ohms)
  3. Inspect wiring to sensor
  4. Check PCM heater control output

Repair notes

Replace O2 sensor if heater resistance is out of spec. Check fuse and wiring first.

🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
As an Amazon Associate, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.

Other Powertrain codes on this vehicle

🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
Stuck on this repair? Take it to The Diag Desk — ask a master tech about this exact car → real human answer within 24h, never AI
🔓 LIBERATED FOREVER
The 2015 Kia Forte 1.8L I4 repair data is free for every DIYer and shop on earth, permanently, because Simon-Olivier Ricci paid $99 to unlock it.
Mitchell1 charges $169/mo for this. ALLDATAdiy charges $30/yr per vehicle. Open Labor Project is free permanently, because of community sponsors like Simon-Olivier.
Free another vehicle →
Building an app?
Free API access to all this data — 10 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →