U0026high severityNetwork
Control Module Communication Bus B Low
on 2007 Lexus GS 430 4.3L V8 · RWD
What this code means
The B communication bus voltage is reading too low, which disrupts data sharing between modules. This can cause multiple systems to lose communication with each other.
Symptoms
- Warning lights on dash
- Multiple systems malfunctioning
- Intermittent module dropout
Common causes
- Shorted bus B wiring to ground
- Corroded or loose connectors
- Failed control module on bus B
- Damaged wiring harness
Diagnostic steps
- Scan all modules for stored codes
- Inspect bus B wiring for shorts
- Measure bus B voltage with scope
- Isolate modules to find fault source
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Serious DIY~$100
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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