mcwrench52

Anybody have this problem??? IS it the a/c amplifier?? Had somebody tell me to look at the relay for the a/c clutch??? Any help PLEASE???

youngtoyotatech

Pulling a/c clutch relay wont help. For a temporary solution you disconnect at the blower when you dont want it on. It is the 2 pin connector going into the bottom of the heater box below the glove box. Not sure if it has an amplifier or just a resistor. Will have to look it up

mcwrench52

Thanks for the info Youngtoyotatech! I actually found the problem this weekend. This truck has the automatic HVAC system in it.
The blower motor has three wires to it:
Blue- 12 volt batt
White/ black trace- dedicated ground
Both of these wires are 10 gauge I think.

Light green/ black trace- signal wire from the blower switch (14 gauge)

I had batt. power and ded. ground, and the signal from the switch (which works like a rheostat on these vehicles) did vary in resistance as you turned the blower switch, gradually decreasing resistance as you turn up the fan speed.
The blower motor has a logic board built into it. took it off of the blower motor and lo and behold there was a burnt spot right in the middle of the board.

I remembered that the power to the blower is KO/KOFF. With the logic board shorted to ground, it wasn't any wonder it ran all the time!!
Hope this helps somebody.....then again I hope nobody runs into this problem!!!!