C0261

Defective CAN Communication

Severity

🔴 High

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–222 (est.)

Symptoms

Check Engine light comes on
Incorrect operation of several vehicle systems
Lost connection with diagnostic equipment
Dashboard malfunctions

Causes

Open or short circuit in the CAN bus wiring harness
Corrosion or poor contact in connectors
Malfunction of one of the modules connected to the CAN bus
Problems with power supply of CAN modules
Damage to CAN bus terminators

How to Fix

Conduct CAN bus diagnostics using an oscilloscope or scanner
Check the integrity of the wiring harness and connectors
Check the resistance on the CAN bus (should be about 60 ohms between CAN-H and CAN-L)
Disable modules one by one to identify the faulty component
Replace damaged wires or faulty module

Related codes

U0100 U0121 U0140