U0014 code meaning
Medium Speed CAN Communication Bus (+) High
What U0014 means
U0014 means CAN-High of the medium-speed bus lies above its normal range, most often because the (+) wire touches battery voltage. On a differential CAN of the high-speed type this is a fault the network rides through: onsemi and NXP found frames still being delivered, but with shifted levels, reduced noise margin and higher current draw in the transceivers. NXP calls such a short hidden because only transceivers with built-in diagnosis notice it. On the comfort bus the result tends to be subtle: an occasional unresponsive switch, a flickering display or a stored code without complaint. No manufacturer documents U0014 publicly, and Saab's description shows only the two-wire terminated layout that makes this analogy plausible. A CAN-High reading close to battery voltage with ignition on confirms the short.
U0014 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0014
- Occasional unresponsive switches or flickering displays
- Stored code without obvious malfunction
Common causes of U0014
- Most likelyMedium-speed CAN-High rubbing against a supply wire
- PossibleMoisture in a door or roof connector linking CAN-High to plus
- Less likelyAftermarket device wired to the comfort bus incorrectly
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
CAN high wireModule connector
What each part of U0014 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 14 | The exact fault in that area. |
What to do next
- Note U0014 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 U0014
What does U0014 mean?
U0014 means "Medium Speed CAN Communication Bus (+) High". U0014 means CAN-High of the medium-speed bus lies above its normal range, most often because the (+) wire touches battery voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with U0014?
U0014 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0014 fail an emissions test?
U0014 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 U0014 to fix?
Difficulty: medium. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will U0014 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.