Check The Power Source Circuit

Disconnect the connector from the ESP control module.
Switch "ON" the ignition, and measure the voltage between terminal 29 of the ESP control module harness side connector and body ground.
Specification: approximately B+

Fig 1: Measure Voltage Between Terminal 29 Of ESP Control Module Harness Side Connector & Body Ground
Courtesy of KIA MOTORS AMERICA, INC.
Is the voltage within specification?
YES
- Check the ground circuit.
NO
- Check the harness or connector between the fuse (10A) in the engine compartment junction block and the ESP control module. Repair if necessary.