U1051high severityNetwork
Brake Switch Circuit Fault
on 2004 Ford Thunderbird 3.8L V6 · FWD
What this code means
The brake switch signal shared across the network is missing or out of range. This can disable cruise control and affect shift interlock and braking functions.
Symptoms
- Cruise control disabled
- Brake lights not working
- Shifter won't move out of park
Common causes
- Faulty brake light switch
- Blown brake circuit fuse
- Damaged switch wiring or connector
- Failed receiving module
Diagnostic steps
- Scan for stored brake circuit codes
- Check brake switch signal in live data
- Test brake switch continuity and adjustment
- Inspect fuse and circuit wiring
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ANCEL AD410 →
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Serious DIY~$100
BlueDriver Pro →
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Autel MaxiCOM MK808S →
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Autel MaxiSys MS906 Pro →
Full-system pro platform — topology mapping, ECU coding, the works.
✓ Autel official store
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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