U0035: Vehicle Communication Bus A (-) High
Severity
Medium
System
Network Communication
What Does U0035 Mean?
U0035 is a diagnostic trouble code indicating: Vehicle Communication Bus A (-) High. This code relates to the network communication system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.
Symptoms of U0035
- ⚠️ Check Engine Light (MIL) illuminated
- ⚠️ Vehicle Communication Bus A (-) High not functioning as expected
- ⚠️ Related system may be in fail-safe mode
- ⚠️ Multiple warning lights on dashboard
Common Causes
- 🔍 Faulty Vehicle Communication Bus A (-) High
- 🔍 Wiring or connector issue in Vehicle Communication Bus A (-) High circuit
- 🔍 Related mechanical or electrical fault
- 🔍 ECM/PCM issue (rare)
Frequently Asked Questions
What does U0035 mean?
U0035 indicates: Vehicle Communication Bus A (-) High. The vehicle's computer has detected that the Vehicle Communication Bus A (-) High is not operating within its expected parameters and stored this diagnostic trouble code.
Can I drive with code U0035?
You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with U0035 for extended periods may cause additional problems.
How much does it cost to fix U0035?
Repair costs for U0035 typically range from $100 to $500, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.
What To Do Next
Possible Fixes
- 🔧 Inspect Vehicle Communication Bus A (-) High and related wiring
- 🔧 Replace faulty Vehicle Communication Bus A (-) High
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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.
Related Codes
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus (-) shorted to Bus (+)
U0010
Medium Speed CAN Communication Bus