U0029

Vehicle Communication Bus A Performance

Severity

🔴 High

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$6–111 (est.)

Symptoms

Check Engine Light Is On
Malfunctions of various vehicle systems
Lost connection with some modules
Incorrect dashboard readings
Problems with diagnostics via OBD-II

Causes

Broken or damaged CAN bus wires
Short circuit in CAN circuit
Fault in one of the modules connected to the bus
Poor contact in CAN bus connectors
Problems with module power supply

How to Fix

Check the integrity of the CAN bus wiring
Inspect connectors and contacts for corrosion
Check voltage in CAN circuit
Disable the modules one by one to find the faulty one.
Update ECU software

Related codes

U0001 U0028 U0030