What it means
A fault is detected between the positive and negative conductors of vehicle communication bus F. Which functions are affected depends on the vehicle’s network design.
How it works
Bus F uses positive and negative conductors to carry messages between its connected modules. This code indicates an electrical short between those two conductors, which can collapse the communication signal and disrupt the bus F network.
Common causes
Most likely first.
- Bus F conductors shorted together
- Damaged or corroded connector
- A module fault
Symptoms
- Communication faults in modules using bus F
- Warning lights or messages
- Functions relying on bus F may be unavailable
How to diagnose it
- Scan all modules for bus F communication codes and save freeze-frame data to identify when the short was detected and which modules stopped communicating.
- Use the vehicle network diagram to trace both bus F conductors and locate their shared connectors, splices, and module connections.
- Inspect areas where the positive and negative wires run together for crushed or chafed insulation, corrosion, water intrusion, or connector damage.
- With power isolated as specified by the manufacturer, test for an unintended connection between the bus F positive and negative conductors.
- If the harness and connectors are sound, follow the manufacturer's isolation procedure to check modules or gateways that may internally short the two lines.
Common fixes
- Clean and secure a corroded or loose bus F connector.
- Separate and repair damaged insulation where the positive and negative wires have contacted.
- Repair or replace a connector with bridging, corrosion, or damaged terminals.
- Repair or replace a confirmed module or gateway shorting the bus F conductors.
Can I keep driving?
Driving may be possible only if the vehicle remains controllable and the affected bus F functions are noncritical; the short can cause more modules or features to drop offline. Do not drive if braking, steering, powertrain, or other essential systems are affected.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.