U0018moderate severityNetwork
Control Module Communication Bus A High
on 2015 Ford Transit Connect 2.5L I4 · FWD
What this code means
Voltage on communication bus A is too high, interfering with data exchange. Modules can drop offline.
Symptoms
- System faults
- Warning lights on
- Intermittent dropout
Common causes
- Bus A shorted to power
- Faulty control module
- Corroded connectors
- Damaged harness
Diagnostic steps
- Scan network
- Measure bus A voltage
- Inspect for short to power
- Isolate 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