U352A code meaning
High Voltage System Interlock Circuit H Performance
Network system Generic code U35xx codes Check engine light
What U352A means
U352A says the eighth loop is closed but its electrical values leave the calibrated band. In CATL's interlock patent the decision thresholds follow from the loop current, a sensing resistor and the impedance of every HV part in the chain. A long loop through many parts therefore has narrow margins: each extra contact, a replacement part with different internal resistance or a lengthened harness shifts the result. That makes a performance fault on a late loop plausible after repairs or conversions. No maker publishes U352A. Compare part numbers of recently fitted HV parts with the originals and look for added plugs in loop H.
U352A 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 U352A
- Fault appears after a repair or conversion
- High-voltage system switches off occasionally
Common causes of U352A
- PossibleReplacement HV component with different interlock resistance fitted
- PossibleExtra connector or harness extension added to loop H
- PossibleRising contact resistance at several loop H terminals
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hvil loop h
What each part of U352A means
| U | Network system: communication between the control modules (CAN bus). |
| 3 | Reserved range, usually generic. |
| 2A | The exact fault in that area. |
What to do next
- Note U352A 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 U352A
What does U352A mean?
U352A means "High Voltage System Interlock Circuit H Performance". U352A says the eighth loop is closed but its electrical values leave the calibrated band. It is a generic code, so it means the same on every make.
Is it safe to drive with U352A?
Drive gently and only to a workshop. With U352A the car can go into limp mode (reduced power) to protect itself.
Will U352A fail an emissions test?
U352A 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 U352A to fix?
Difficulty: workshop only. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will U352A clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.