Free API
P0115moderate severityPowertrain

Engine Coolant Temperature (ECT) Sensor 1 Circuit

on 2015 Kia Forte 1.8L I4 · FWD

What this code means

General malfunction in the engine coolant temperature sensor circuit.

Symptoms

  • Check Engine Light
  • Poor fuel economy
  • Hard starting
  • Incorrect temp gauge reading
  • Fans not operating correctly

Common causes

  • Faulty ECT sensor
  • Wiring damage
  • Corroded connector
  • Low coolant level

Diagnostic steps

  1. Test ECT resistance at known temperature
  2. Inspect wiring
  3. Check coolant level
  4. Compare ECT to IAT at cold start

Repair notes

Replace ECT sensor or repair wiring. Verify coolant level.

Other Powertrain codes on this vehicle

For shop owners
Diagnosing for customers?
Text them the estimate with photos and get approval in minutes with Auto Shop Base.
Talk to the ownerSee what's included
Built by a shop owner. Talk to Chris, not a sales rep.
🔧 Built by master technician Chris Hackleman · Master Technician · 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?
A free website, SEO and Google reviews with your shop software. Auto Shop Base Professional, $250/mo, with our labor times on every estimate.
See what's included →