U0427low severityNetwork
Invalid Data Received From Fuel Fired Heater Control Module
on 2023 Chevrolet Bolt EUV 65 kWh Single Motor FWD · FWD
What this code means
The vehicle's network is receiving corrupt or implausible data from the fuel fired (auxiliary) heater control module. This usually points to a communication fault or a problem inside the heater module itself.
Symptoms
- Auxiliary heater not working
- Warning light on dash
- Poor cabin or engine heating in cold weather
Common causes
- Faulty fuel fired heater control module
- Wiring or connector corrosion at module
- CAN bus communication fault
- Low battery voltage or bad ground
Diagnostic steps
- Scan all modules for related U-codes
- Check heater module wiring and connectors
- Verify power and ground at module
- Test CAN bus signals for the module
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Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus