Back to 2017 GMC Terrain
Help

2017 GMC TERRAIN

2.4L I4•FWD•AUTOMATIC•gas
1 active safety recall on this vehicle — view recalls
Founding sponsor spot is openYour name on every procedure for this vehicle, permanently.Sponsor — $99 →
Repairs0Labor564Torque2394Fluid6DTC969Battery0Maintenance0Recalls1
P1115moderate severityPowertrain

ECT Sensor Circuit Intermittent High Voltage

on 2017 GMC Terrain 2.4L I4 · FWD

What this code means

The PCM detected intermittent high voltage on the Engine Coolant Temperature sensor circuit, indicating the sensor is sporadically reporting very low temperatures.

Symptoms

  • Check Engine Light
  • Rich running condition
  • Poor fuel economy
  • Cooling fans not activating when needed

Common causes

  • Intermittent open in ECT circuit
  • Loose ECT connector
  • Faulty ECT sensor
  • Corroded terminals

Diagnostic steps

  1. Monitor ECT readings for erratic spikes
  2. Wiggle test ECT connector
  3. Test sensor resistance across temperature range
  4. Check connector terminals

Repair notes

Clean and secure ECT connector. Replace sensor if faulty.

Other Powertrain codes on this vehicle

⚠ STILL BEHIND THE PAYWALL
The 2017 GMC Terrain repair data is incomplete because no one has sponsored it yet. For $99, we generate the full step-by-step procedures, then fact-check them with a second AI pass and your expert review. Your name on every procedure, permanently.
The same data would cost $169/mo from Mitchell1 or $30/year from ALLDATAdiy — and you'd be renting access, not freeing it. Sponsor once, free forever.
Sponsor the GMC Terrain — $99 →
Building an app?
Free API access to all this data — 50 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 →