U04A6 code meaning
Invalid Data Received From Hybrid/EV Battery Interface Control Module F
Network system Generic code U04xx codes Check engine light
What U04A6 means
U04A6 is set when interface control module F delivers messages the battery controller cannot accept. A board like this checks itself as well: in GM's 16OBDG02 table every interface module, F included, runs four processor performance tests once at each ignition change, for example confirming that its analogue-to-digital converter shows no stuck bits when the input is forced to its limits, Type A after 8 failures in 10 samples. Such internal faults get their own GM P1 codes; U04A6 is meant for the case where the receiver itself judges the incoming data unusable. No manufacturer documents U04A6 publicly. U01A5 means F has stopped talking, U033F that its software does not fit. Expect a hybrid or EV warning and restricted output.
U04A6 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1.5 to 8 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U04A6
- Hybrid or EV warning, MIL on plug-in hybrids
- Reduced power output
Common causes of U04A6
- PossibleProcessor or converter fault on interface board F
- PossibleContact fault on the internal data link to module F
- Less likelySupply dropouts of the battery electronics during switch-on
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 f
What each part of U04A6 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A6 | The exact fault in that area. |
What to do next
- Note U04A6 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 U04A6
What does U04A6 mean?
U04A6 means "Invalid Data Received From Hybrid/EV Battery Interface Control Module F". U04A6 is set when interface control module F delivers messages the battery controller cannot accept. It is a generic code, so it means the same on every make.
Is it safe to drive with U04A6?
Drive gently and only to a workshop. With U04A6 the car can go into limp mode (reduced power) to protect itself.
Will U04A6 fail an emissions test?
Yes, it can. U04A6 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 U04A6 to fix?
Difficulty: workshop only. A typical repair takes 1.5 to 8 hours of work. This is a job for a workshop.
Will U04A6 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.