P1126moderate severityPowertrain

Thermostat Function

on 2018 Infiniti Q70L 5.6L V8 · RWD

What this code means

Engine coolant temperature not reaching expected operating temperature.

Symptoms

  • CEL
  • Engine runs cold
  • Poor efficiency
  • Weak heater
  • Slow warm-up

Common causes

  • Thermostat stuck open
  • Faulty ECT sensor
  • Air in cooling system
  • Low coolant

Diagnostic steps

  1. Monitor coolant temp
  2. Test thermostat
  3. Check ECT sensor
  4. Inspect cooling system

Repair notes

Replace thermostat.

Other Powertrain codes on this vehicle

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