Don't overlook the obvious. Have you tried new bulbs? It wouldn't be the first time both bulbs burned out at the same time. It is just low beams? Do the high beams work? Did you check the fuses in the TIPM under the hood? Did you consult the owner's manual to see where the fuses are or troubleshooting?
There may or may not be headlamp fuses and instead the headlamps may be controlled by solid-state drivers inside the TIPM. As suggested, check the bulbs first.
If the TIPM detects a short in the headlamp circuit, it will turn off that circuit for protection. A fault code will be stored and once the short is lifted and the TIPM cycled, then headlamp operation will be restored.
If the headlamp switch fails, the headlamps will default to staying on for safety.
The fog lamps still work on a relay.