U0099

Vehicle Communication Bus H (-) High

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$6–56 (est.)

Symptoms

Check Engine light comes on
Incorrect operation of the vehicle's electronic systems
Loss of communication between modules
Reduced engine performance
Errors in other systems

Causes

Open or short circuit in wiring harness
Damage to communication bus connectors
Malfunction of one of the control modules
Grounding problems
Electromagnetic interference

How to Fix

Check the integrity of the communication bus wiring harness
Inspect connectors for corrosion or damage
Check module grounding
Scan all modules for errors
Replace damaged components if necessary

Related codes

U0100 U0101 U0098