U0440moderate severityNetwork
Invalid Data Received From Gateway 'A'
on 2002 Ford Explorer 4.0L V6 SOHC · RWD
What this code means
A module received corrupted or implausible data from the gateway module 'A'. This can affect any systems that rely on data routed through the gateway.
Symptoms
- Multiple module fault codes
- Erratic system operation
- Warning lights on dash
Common causes
- Faulty gateway module
- CAN bus wiring fault
- Software or calibration mismatch
- Poor connector contact
Diagnostic steps
- Scan network for related communication codes
- Inspect gateway module power and grounds
- Check CAN bus wiring for shorts or opens
- Verify module software compatibility
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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