U0029: Vehicle Communication Bus A Performance
What Does U0029 Mean?
U0029 is a diagnostic trouble code indicating: Vehicle Communication Bus A Performance. This code relates to the network communication system. It has been reported in NHTSA complaints across 3 different vehicle models.
Symptoms of U0029
- ⚠️ ABS warning light on
Common Causes
- 🔍 Sensor or control module malfunction
U0029 Reports by Year
Real Owner Reports
From NHTSA complaint database — actual owner descriptions.
"I WAS DRIVING THE CAR TO WORK AND THE ABS LIGHT AND RED BRAKE LIGHT CAME ON IN THE DASHBOARD. ALSO, THE RPM GAUGE WAS GOING UP AND DOWN. I STOPPED AND TURNED OFF THE CAR. WHEN I TURNED THE CAR BACK ON, THE LIGHTS CAME BACK. I TOOK IT INTO JUST A JIFFY LUBE BECAUSE IT WAS THE CLOSEST CAR PLACE NE"
— Toyota Camry owner, 04/03/2014
"Driving down highway at highway speed and car shot 52 failure codes. Car lost power and crawled to side of road. Nearly got rear ended multiple times trying to remove vehicle from roadway. Engine permanent codes U0111 U012D U0110 U12A5 U1206 U1205 Anti lock brakes permanent codes U040168 CAN "
— Honda Insight owner, 12/09/2022
Source: NHTSA Complaints Database
Most Reported Vehicles for U0029
Based on NHTSA owner complaint data.
| # | Vehicle | Reports |
|---|---|---|
| 1 | TOYOTA CAMRY | |
| 2 | HONDA ACCORD | |
| 3 | HONDA INSIGHT |
Frequently Asked Questions
What causes communication codes?
Can a bad battery cause network codes?
What To Do Next
Possible Fixes
- 🔧 Have the code scanned with a professional-grade scanner to read freeze frame data
- 🔧 Test the relevant sensor(s) with a multimeter before replacing
- 🔧 Check battery voltage and ground connections; inspect CAN bus wiring
- 🔧 If DIY repair isn't feasible, get a diagnostic from a trusted mechanic ($50-150)
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1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
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2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
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3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.