2008 Tahoe blower fan problem

[conmax]

i have a 2008 tahoe with climate control. the A/C blower/fan motor shuts off after running for a variable time period. on a hot day, it will shut off in a very short time, like 5 minutes. it takes longer on coller days, but still needing AC.

 

the gmt 9000 platform uses a fan controller module, rather than a simple resistor pack on earlier models.

 

i have replaced that module with a new one that does the same thing.

 

the voltage across the blower motor drops from 12v down to 3v over time, at which point the fan stops.

 

the plemnun where the module sits is very hot. i wonder if this area should be quite hot and still allow the module to function.

 

if i disconnect the black motor wire from the module and ground it, the fans runs at high speed.

[gmtech4]

do you have service information and a scanner ?