B1024low severityBody
A/C Evaporator Temperature Sensor Circuit High
on 2020 Chevrolet Express 6.0L V8 Vortec · RWD
What this code means
The HVAC module sees high voltage on the evaporator temperature sensor circuit, meaning an open or short-to-power. No exact OBD P-code equivalent (similar to P0535).
Symptoms
- A/C not cooling properly
- Erratic HVAC operation
- Fan runs but weak cold air
Common causes
- Faulty evaporator temp sensor
- Open in sensor wiring
- Short to power on signal wire
- Corroded connector
Diagnostic steps
- Check sensor connector for damage
- Measure sensor resistance vs spec
- Check signal wire for short to power
- Test HVAC module reference voltage
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Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0006
Passenger Knee Airbag Deployment Circuit
B0007
Rear Left Side Airbag Deployment Circuit
B0008
Rear Right Side Airbag Deployment Circuit
B0009
Rear Center Airbag Deployment Circuit
B0010
Driver Side Airbag Deployment