U0055

Vehicle Communication Bus D

Q: Is it safe to drive with U0055?

Usually yes short-term, but features on Bus D may be unreliable. If systems quit or lights multiply, get it checked.

Q: Can I just clear U0055?

It returns if the bus fault is still present. Repair the wiring or module first, then clear and retest.

Data bus (CAN) Generic OBD-II Medium

What it means

U0055 is a general fault on Communication Bus D — a module has detected a problem with this data bus but not a specific short or open. Bus D is one of the vehicle's manufacturer-defined networks; when it's disrupted the modules on it can stop exchanging data, causing warning lights and lost features.

Medium

Can I keep driving? Usually drivable for now, but the systems on Bus D may act up or quit and warning lights can appear; have it diagnosed soon.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Appears alongside · share of U0055 scans

U0064in 77.2% of scans

B0093in 67.1% of scans

B0098in 67.1% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Warning lights on for one or more systems
Modules on Bus D dropping off the scan tool
Intermittent or lost function of Bus D features
Additional U-codes stored alongside

Common causes

Most likely first

Damaged or corroded Bus D wiring or connectorLikely
Water intrusion in a harness connectorCommon
A failed module disrupting the busCommon
Loose power or ground to a bus moduleLess often
Damaged terminating resistorLess often

How to diagnose & fix

Work through it in order

Scan all modules and record the communication codes.
Check battery voltage and charging before diagnosing the bus.
Inspect Bus D wiring and connectors for damage, corrosion, or moisture.
Measure bus resistance key-off (about 60 ohms on a terminated bus).
Disconnect modules one at a time to isolate a unit disturbing the bus.

FAQ

Quick answers

Is it safe to drive with U0055?+

Usually yes short-term, but features on Bus D may be unreliable. If systems quit or lights multiply, get it checked.

Can I just clear U0055?+

It returns if the bus fault is still present. Repair the wiring or module first, then clear and retest.

Read & clear U0055 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX