U0045

Vehicle Communication Bus B (-) shorted to Bus B (+)

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$6–56 (est.)

Symptoms

Unstable engine operation
Failure of various vehicle systems
Check Engine Light Is On
Problems starting the engine
Lost connection with diagnostic equipment

Causes

Damage to the CAN bus wiring harness
Short circuit in one of the modules
Corrosion of connector contacts
Mechanical damage to wiring
Control unit malfunction

How to Fix

Visual inspection of the CAN bus wiring harness
Checking the resistance between CAN B+ and CAN B- lines
Disabling modules one by one to identify faults
Replacing damaged wires or connectors
Repair or replacement of a faulty module

Related codes

U0046 U0047 U0048