Temperature Control Switch

Found the problem. First everything checked out fine switch , circuit breaker, relays , the problem was there is a connector between the fan and fuse board located behind the cowling above the fan blower motor. I assume is was never fully pressed together and took 280000 miles to finally jiggle loose. When it first started going out and I would tap the cowling it must have been enough to complete the circuit and run. Then it finally loosened itself completely and no longer powered resistor or fan. Wish I would have worked from the fan back vs switch down.
That's one for the books and I now have spare relays and a fan motor :)
Donny

Quote:

---

Originally Posted by beoutside

Thanks Tim
yes no power at motor wires or at resistor 12 v setting on my fluke ground at battery ,will check connections as you suggest.
Donny

---

Replacing all dash board bulbs ( LED) and heater panel ones as well anyways :)

Quote:

---

Originally Posted by beoutside

Found the problem. First everything checked out fine switch , circuit breaker, relays , the problem was there is a connector between the fan and fuse board located behind the cowling above the fan blower motor. I assume is was never fully pressed together and took 280000 miles to finally jiggle loose. When it first started going out and I would tap the cowling it must have been enough to complete the circuit and run. Then it finally loosened itself completely and no longer powered resistor or fan. Wish I would have worked from the fan back vs switch down.
That's one for the books and I now have spare relays and a fan motor :)
Donny

---

That's a relief I'm sure. I fixed a similar on my 86 van last week. Connection point on back of the fuse box burned. I was so sure it was a bad motor I had already purchased one to put in. Before I swapped it out I checked for power at the motor leads and found there was none. When I reached up to wiggle the heater relay it started running again. I popped out the fuse box and a close inspection of the back revealed a pin/wire that looked a lot like TheMan's picture of his switch connection. Fortunately I have a parts van and those parts were in good shape on that. Tim

awesome... I'm surprised you only found this out now... what did you do to replace the fan motor? I took the entire blower box out to do mine, which meant also disconnecting that sub-harness just above the evaporator

I thought it was a very bad problem because the front fan panel and the rear ac unit would not turn on. It was like it had no power. I then went to the fuse panel in the center of the dashboard and from there I checked the different fuses and I saw that the ac fuse was broken in the middle. The diagram of the fuses is on the center panel once the top is taken off. I replaced the fuse with the spare one in there and it worked good. The front fan and ac plus the rear fan/ac unit started working.

Quote:

---

Originally Posted by terbennett

Hi-
My 1991 Toyota Previa's A/C just stopped working. I was told that it is a temperature control switch that is located deep in the dash. Is this true? I just had the expansion valves, blower fan and compressor replaced. Now the blower fan stopped working I was told that it is a temperature control switch that is recessed deep in the dash. For some reason I think the mechanic lied to my wife. Could someone tell me if this switch exists?

---