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Hi,
I am hoping someone has some electrical insight to a problem I'm having. Is a 1991 4runner a/t 3.0
I am working on getting the ac working but I am having one problem, the condenser fan will not turn on. Everything else works fine.
the number 2 relay if jumped will turn on the fan. The problem is it's only getting .12 volts to the charge side of the relay it's not enough to set it off.
So I've also tested the wiring harness side on the ac amplifier and from spot 2-7 ( 7 is ground from what I can understand ) I get the same .12 volts with fan speed on low and ac button depressed. But it I turn the fan to high I get .60 volts. Still not enough to trip the rrelay
My firstguess is something in the fan speed controls limiting voltage but I have no clue.
I don't believe the 1991s came stock with a condenser fan (that would be in front of the radiator). You could have an after-market addition, or you could be talking about the evaporator fan (under the dash).
What is "number 2 relay"? The heater relay controls the heater fan (which is what pulls air through the evaporator). What is the "charge side" of a relay? The coil?
The AC amplifier has no connection to the Blower Switch, so if changing the blower switch affects the voltage on the amplifier connector, you've got a cross-connection somewhere.
It is a 1991 Vin and it looks very much factory I suppose it could have been swapped in but I doubt it. All the wiring for the condenser is there. Forgot to mention it is 4x4 auto v6
The number 2 condenser fan relay as labeled in a few diagrams I could find. The middle relay in between the 30 amp break for the condenser fan and the number one relay as far as I can tell. Yes I meant the coil of the relay. Its not getting energized with 12v when I click the ac on. Although the clutch and everything work fine.
According to a pin out I found 2 to 7 should have 12 volts with key on ac on fan high. It doesn't it has something around .2 volts. Same as the coil on relay no 2.
i'm using this picture, so i think i've narrowed it down but i still dont know what to do next
Last edited by roll121212; 08-04-2016 at 08:49 AM.
Apparently you were right Marc. The fan doesn't come on for me until about 1000 rpm and running temp coolant. One of those things did the trick.. And possibly the thermistor had something to do with it.
I also found the resistor driver side in front of radiator was missing and it wouldn't come on until that was jumped. I think I'll just leave it jumped until I get a new resistor.
08-04-2016, 05:58 AM
