Different description of Hyundai Elantra OBDII code P1502

thermostat2

My car is Hyundai Elantra 2003, 180KM. The check engine light pops on recently. The code is P1502.
dtcsearch.com shows
P1502 – Hyundai, Wheel speed sensor - open circuit
http://www.dtcsearch.com/P1502/

but engine-code.com shows
P1502 Hyundai - Battery Not Charging
http://engine-codes.com/p1502_hyundai.html


Which one is the correct description of Hyundai P1502?

Thanks.