U350A code meaning
Control Module Input Power C Circuit High
Network system Generic code U35xx codes Check engine light
What U350A means
U350A is the overvoltage code for supply C. GM's electric brake booster (2016–2019 hybrid tables) logs it when voltage sensor 2 on the motor driver supply exceeds 19.8 V for 90 s at speeds above 4 mph, Type A, so a single failing trip lights the MIL. The limit is higher than the 16 to 18 V thresholds used for feeds A and B because the motor stage tolerates more, yet a lasting excess is treated as serious since it threatens the power transistors. The pass condition is a straight drive over 3.1 miles or more. Such values rarely arise in a healthy 12 V system: think of a failed generator regulator or DC/DC converter, jump-starting from a 24 V source, or, with normal battery voltage, an internal sensing error.
U350A at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of U350A
- MIL and brake warning on the first trip
- Brake assist reduced or switched off
Common causes of U350A
- PossibleGenerator regulator or DC/DC converter overcharging
- PossibleJump start from a 24 V source
- PossibleFaulty measurement of feed C inside the module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Module power cCharging system
What each part of U350A means
| U | Network system: communication between the control modules (CAN bus). |
| 3 | Reserved range, usually generic. |
| 0A | The exact fault in that area. |
What to do next
- Note U350A 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 U350A
What does U350A mean?
U350A means "Control Module Input Power C Circuit High". U350A is the overvoltage code for supply C. It is a generic code, so it means the same on every make.
Is it safe to drive with U350A?
Drive gently and only to a workshop. With U350A the car can go into limp mode (reduced power) to protect itself.
Will U350A fail an emissions test?
U350A 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 U350A to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U350A clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.