U0038low severityNetwork
LIN Bus A (+) Open
on 2019 Mazda Mazda3 2.5L I4 · FWD
What this code means
The LIN bus A wire is open, preventing communication with LIN slave devices.
Symptoms
- LIN-connected devices inoperative
- Seat memory not working
- Rain sensor offline
- Interior lighting module offline
Common causes
- Broken LIN bus wire
- Corroded LIN connector
- LIN module unplugged
- Wiring harness damage
Diagnostic steps
- Check LIN bus wire continuity
- Inspect connectors
- Test for 12V pullup on LIN bus
- Check LIN master output
Repair notes
Repair open LIN bus wire. Check connectors at all LIN slave devices.
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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