P1400moderate severityPowertrain
Cold Start Emission Reduction Control System
on 2023 Chevrolet Bolt EUV 65 kWh Single Motor FWD · FWD
What this code means
The cold start emission control system is not performing as expected. This affects emissions during engine warm-up.
Symptoms
- Check engine light on
- Failed emissions test
- Slightly rough cold running
Common causes
- Faulty coolant temperature sensor
- Stuck idle air control
- Timing control fault
- Wiring or connector issue
Diagnostic steps
- Scan for stored codes
- Monitor cold start emission parameters
- Check coolant temp sensor readings
- Inspect related wiring and actuators
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Other Powertrain codes on this vehicle
P0070
Ambient Air Temperature Sensor Circuit
P0071
Ambient Air Temperature Sensor Range/Performance
P0072
Ambient Air Temperature Sensor Circuit Low
P0073
Ambient Air Temperature Sensor Circuit High
P0115
Engine Coolant Temperature (ECT) Sensor 1 Circuit
P0116
ECT Sensor 1 Circuit Range/Performance
P0117
ECT Sensor 1 Circuit Low Input
P0118
ECT Sensor 1 Circuit High Input
P0119
ECT Sensor 1 Circuit Intermittent
P0125
Insufficient Coolant Temperature for Closed Loop Fuel Control