Report: CIAIAC publishes final report on fatal MD-82 takeoff accident Madrid, Spain « Aviation Safety Network's News
It's been over 3 years and they just came out with this final report. It doesn't help much. The R2-5 relay was the air/ground sensor getting it's information from the nose gear strut. It sensed air mode so the probe heater was hot causing their return for maintenance. The air mode was also thought to be why they had no TOWS since it was powered through the same relay. I agree, maintenance didn't disable it, they just didn't realize it was inop when they disabled the probe heater by pulling it's CB as I remember.
A couple of years ago someone posted a schematic of the circuits involved on this thread.