U0094 code meaning
Vehicle Communication Bus H (+) Open
What U0094 means
U0094 reports that the (+) wire of Bus H is interrupted, CAN-High where Bus H is a CAN. No manufacturer documents U0094 publicly. How much the break matters depends on the kind of CAN. A fault-tolerant low-speed CAN up to 125 kBd, built with transceivers such as NXP's TJA1055, keeps receiving differentially with a broken CANH wire, and the chip's error output toggles only if the gap separates the sending node from the listening one, so the module may see the fault only now and then. A high-speed CAN loses the far nodes. For locating it, Nissan's chart separates a break in the main line from one in a branch to a single module, judged by the resistance and voltages measured at the diagnostic socket.
U0094 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyHard
- Typical labor0.5 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0094
- Single modules on Bus H not reachable
- Fault appears intermittently or with movement
Common causes of U0094
- Most likelyBroken (+) wire, e.g. at a hinge or flexing harness section
- PossibleTerminal pushed out of a connector
- Less likelyCorroded splice with high resistance
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Bus h wiringCAN high wire
What each part of U0094 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 94 | The exact fault in that area. |
What to do next
- Note U0094 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0094
What does U0094 mean?
U0094 means "Vehicle Communication Bus H (+) Open". U0094 reports that the (+) wire of Bus H is interrupted, CAN-High where Bus H is a CAN. It is a generic code, so it means the same on every make.
Is it safe to drive with U0094?
U0094 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0094 fail an emissions test?
U0094 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U0094 to fix?
Difficulty: hard. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will U0094 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.