U0039
LIN Bus A (-) Open
2003-2009 Toyota 4Runner 4.7L V8
Low SeverityNetworkGeneric (SAE)
Description
The LIN bus A ground reference is open, preventing proper LIN communication.
Symptoms
- LIN slave devices not responding
- Erratic LIN device behavior
Common Causes
- LIN ground wire open
- Corroded ground connection
- Broken ground splice
Diagnostic Steps
- Check LIN ground continuity
- Inspect ground connection points
- Test for proper ground at LIN devices
Repair Notes
Repair the open ground on the LIN bus circuit.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0005High Speed CAN Communication Bus (+) High
U0039 on Other Vehicles
Toyota 4Runner
2003-2009 4.0L V6
Toyota 4Runner
2010-2024 4.0L V6
Toyota 86
2017-2020 2.0L H4
Toyota Alphard
2023-2025 2.4L I4 Turbo T24A-FTS
Toyota Alphard
2023-2025 2.5L I4 Hybrid A25A-FXS
Toyota Altezza
1998-2005 2.0L I4 3S-GE BEAMS
Toyota Altezza
1998-2005 2.0L I6 1G-FE
Toyota Aqua
2011-2021 1.5L I4 Hybrid 1NZ-FXE
Common Questions
What does code U0039 mean on a 2003-2009 Toyota 4Runner?
U0039 stands for "LIN Bus A (-) Open". The LIN bus A ground reference is open, preventing proper LIN communication.
What are the symptoms of U0039 on a Toyota 4Runner?
Common symptoms of U0039 include: LIN slave devices not responding, Erratic LIN device behavior.
What causes U0039 on a 2003-2009 Toyota 4Runner?
Common causes of U0039 include: LIN ground wire open, Corroded ground connection, Broken ground splice.