Network, generic

U04AE Invalid Data Received From Hybrid/EV Battery Interface Control Module N

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

U04AE stands for invalid data from interface module N, the fourteenth. Like the other high letters it can only appear on a large pack, and no manufacturer documents it publicly. What changes for the workshop is mostly practical: the board sits inside the sealed high-voltage battery, so after reading the freeze-frame data and ruling out the 12 V supply and the low-voltage connectors outside the pack, every further step means de-energising the system, measuring isolation and opening the housing, a job for trained staff with the maker's tester. Polestar, for example, bills a high-voltage battery disconnect with insulation measurement as a labour step of its own when a high-voltage part is replaced. U01AD means module N is silent, U0347 a software conflict.

Likely causes

12 V supply or low-voltage plug of the pack at fault (check first)
Interface control module N faulty
Contact fault on the internal link to module N

Symptoms

  • Battery or EV system warning
  • Output and charging power limited

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€200–4,000
Time2–12 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

hv battery interface module n

Related codes

U01ADU0347U04ADU04AF

References: static.nhtsa.gov, gsi.ext.gm.com, law.cornell.edu.