U352B code meaning
High Voltage System Interlock Circuit H Low
Network system Generic code U35xx codes Check engine light
What U352B means
U352B reports too low a level on interlock loop H. Apart from a pulled plug or a grounded wire, a deliberate opening can cause it: Texas Instruments mentions feeding a crash signal into the loop so that high voltage shuts off after an accident. The DGUV warns that such a crash shutdown does not establish absence of voltage and that disconnection following the maker's rescue sheet is still advisable; FMVSS 305a takes its post-crash voltage readings in a window from 10 s to one minute after the impact. No maker documents U352B. After a collision, replace damaged loop sections rather than patching them, and have trained staff isolate the system.
U352B 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 U352B
- High voltage off after an accident or airbag deployment
- Vehicle cannot be made ready
Common causes of U352B
- PossibleLoop H opened on purpose by a crash signal after an accident
- PossibleLoop H wiring or plug damaged in a collision
- PossibleLoop H wire shorted to ground
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hvil loop hHvil wiring
What each part of U352B means
| U | Network system: communication between the control modules (CAN bus). |
| 3 | Reserved range, usually generic. |
| 2B | The exact fault in that area. |
What to do next
- Note U352B 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 U352B
What does U352B mean?
U352B means "High Voltage System Interlock Circuit H Low". U352B reports too low a level on interlock loop H. It is a generic code, so it means the same on every make.
Is it safe to drive with U352B?
Drive gently and only to a workshop. With U352B the car can go into limp mode (reduced power) to protect itself.
Will U352B fail an emissions test?
U352B 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 U352B to fix?
Difficulty: workshop only. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will U352B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.