U014A code meaning
Lost Communication With Battery Energy Control Module C
Network system Generic code U01xx codes Check engine light
What U014A means
U014A concerns a third battery energy control module, C. Hybrid and electric vehicles use such units to watch cell voltages, temperatures and state of charge and to protect the pack; distributed or modular designs give several sub-packs their own controller, which is where letters beyond A and B come in. No manufacturer documents U014A publicly. The best documented relative is U0111 for module A: in GM's 2018 hybrid tables the hybrid powertrain controller flags missing BECM messages after 500 ms, once bus communication has run for at least 5 s and the battery holds 10.2 V or more, and rates it Type B with MIL after two trips. Without data from C the system cannot judge that part of the pack, so expect reduced power, blocked charging or no ready mode. U0111, U0112 and U014C cover modules A, B and D, U044B invalid data from C.
U014A at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 6 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U014A
- Hybrid or EV system warning, reduced power
- Charging refused or stopped
- Vehicle may not enter ready mode
Common causes of U014A
- Most likelyLow-voltage supply, fuse or ground of battery module C missing
- PossibleBus wiring or connector inside or at the battery pack damaged or corroded
- Less likelyMoisture or coolant in the pack affecting module C
- Less likelyBattery module C internally faulty or not programmed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Battery energy module cCAN bus
What each part of U014A means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 4A | The exact fault in that area. |
What to do next
- Note U014A 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 U014A
What does U014A mean?
U014A means "Lost Communication With Battery Energy Control Module C". U014A concerns a third battery energy control module, C. It is a generic code, so it means the same on every make.
Is it safe to drive with U014A?
Drive gently and only to a workshop. With U014A the car can go into limp mode (reduced power) to protect itself.
Will U014A fail an emissions test?
U014A 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 U014A to fix?
Difficulty: workshop only. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will U014A clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.