P1628moderate severityPowertrain
ECT Pull-Up Resistor
on 2023 Chevrolet Bolt EUV 65 kWh Single Motor FWD · FWD
What this code means
The PCM detected a fault in the engine coolant temperature sensor pull-up resistor circuit. This can cause inaccurate temperature readings.
Symptoms
- Check engine light on
- Poor cold start performance
- Incorrect temperature gauge reading
Common causes
- Faulty PCM
- ECT sensor circuit fault
- Wiring or connector problems
- Corroded ECT connector
Diagnostic steps
- Scan for ECT-related codes
- Inspect ECT sensor and wiring
- Measure ECT signal voltage
- Repair wiring or replace PCM as needed
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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