U0348 code meaning
Software Incompatibility With Hybrid/EV Battery Interface Control Module O
What U0348 means
O stands for a fifteenth board; no public document links U0348 to a vehicle. That the software inside a cell monitoring unit can itself be the problem is shown by Honda's recall 15V602 of October 2015: in 6,786 Accord Hybrids of 2014–2015 the cell voltage sensor (CVS) could misread electrical noise from inverter and motor circuits, a side effect of a change made for digital TV reception in Japan, and switch the car into a fail-safe EV mode limited to about 40 mph, with the engine off. Dealers installed new hybrid system software, which Honda says does not affect emissions or fuel economy. Honda uses no letter codes for the CVS. U01AE flags a silent O, U04AF corrupted data.
U0348 at a glance
- Check engine lightUsually not
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.3 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0348
- Fail-safe mode with reduced speed and power
- Engine switched off, electric drive only until the battery is drained
- Hybrid warning with audible alert
Common causes of U0348
- Most likelyFirmware of the monitoring unit itself faulty and superseded
- PossibleBoard O missed a released software update
- Less likelyPack boards on different update levels after a partial repair
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery interface module o
What each part of U0348 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 48 | The exact fault in that area. |
What to do next
- Note U0348 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 U0348
What does U0348 mean?
U0348 means "Software Incompatibility With Hybrid/EV Battery Interface Control Module O". O stands for a fifteenth board; no public document links U0348 to a vehicle. It is a generic code, so it means the same on every make.
Is it safe to drive with U0348?
Drive gently and only to a workshop. With U0348 the car can go into limp mode (reduced power) to protect itself.
Will U0348 fail an emissions test?
Yes, it can. U0348 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U0348 to fix?
Difficulty: workshop only. A typical repair takes 0.3 to 2 hours of work. This is a job for a workshop.
Will U0348 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.