Might be one of these:
1040 XEGYS Guaymas, Sonora. 12/1 0325 using slogan "Super Banda" but wasn't playing banda, they were playing disco beat grupera. Could there be a format change along with a new slogan? [Redding-AZ]
1040 XEHES Chihuahua, Chihuahua. Jan 25 1155 - Currently the almost-dominant in the phase null of WHO at local dawn. Regularly runs 1 hour or longer programs from Radio Trans-Mundial [North American SS Trans-World Radio] in the 1100-1200+ time slot. The Trans-Mundial programs close with the RT-M office address in Miami repeated twice and a short instrumental segue. On this date, the program closed at 1203 and XEHES gave a full legal ID, followed by the 'Radio Luz' slogan. Some mornings, there is no ID between the close of RTM programming and resumption of local programming. [Bryant-OK]
+ 1/26 2030 caught clear call letter ID in brief WHO null/fade into vocal [religious?] mx, then quickly faded down u/WHO. [Winkelman-OK]
+ NOV 10 0320 strongest ever heard; at times WHO completely nullable. Woman preacher noted at this time. At 0330, after the woman preacher's program ended, Radio Luz played a choral hymn in English, "I Trust In You." At 0413, had another hymn, in Spanish, "Es Amor" and at 0415 had short announcement between hymns, "Radio Luz, diez cuarenta, La Radio Christiana." Better tape than last time, but I've never heard the call letters on this one. [Callarman-TX]
I got this info from
http://www.dxing.info/logs/Mexico_Corazon_2002.doc