Bill_Dunnigan
New member
Does your heat / AC only work on high? Heres how you fix it.
In most vehicles with multiple manual fan speeds, the manufacturers regulate the voltage going to the motor by way of a resistor. By putting different values of resistor before the fan motor, they can limit the amount of voltage the fan sees. This is all fine and dandy until your fan motor starts getting clogged up with pine needles or whatever and draws more current through the resistor pack. more current means more heat which means bye bye fan speeds. The reason the fan still works on high is because the fan is seeing the full 12-14 volts from the battery un-interupted because there is no resistor needed for high speed.
Now that you know why it breaks, let teach you how to fix it!
Step One: Buy a replacement resistor pack from your local toyota dealer or online. The dealer sells the part for about $35, and i have seen it as low as $10 online. I just went with the Toyota dealer, because they had one in stock and its only $35! Here is the new part.
Step Two: Look Underneath the passenger glove-box. Right up front you will see the Resistor pack, or at least the plastic part of it where the harness plugs in. Remove the Harness, Simply squeeze the connector and shimmy it outta there!
Step Three: Unscrew the two Phillips head screws that hold on the resistor pack. The bottom one can be accessed with a regular long screwdriver with the glove box closed. The top screw can be accessed two different ways. You can either use a 1/4 inch ratchet with a socketed Phillips head attachment, or you can open the glove-box and squeeze the inside of it to pull it down further and then you will be able to access the screw with the screwdriver! whew!!!!....that was a long run-on sentence!
Step Four: Remove the resistor pack by pulling it straight out, you might nedd to wiggle it a bit to get it out. (might come out in pieces from heat failure).
As you can see from the picture above, the metal pins are shot! one of them broke a solder and the whole ceramic heat sink is cracked and toasted!
Now, take a flashlight and look inside the cowling (hole that the resistor pack came out of) and make sure there is no debris in there! mine had quite a bit, so I vacuumed it out. I recommend you do the same.
Step Five: Reinstall the new resistor pack in the correct orientation. Be-careful, they can be quite delicate. If it breaks while putting it in, you'll have to buy a new one, because it will surly fail again if it looses some of its heat-sink. Don't forget to plug it back in!
Good Luck, Enjoy!
In most vehicles with multiple manual fan speeds, the manufacturers regulate the voltage going to the motor by way of a resistor. By putting different values of resistor before the fan motor, they can limit the amount of voltage the fan sees. This is all fine and dandy until your fan motor starts getting clogged up with pine needles or whatever and draws more current through the resistor pack. more current means more heat which means bye bye fan speeds. The reason the fan still works on high is because the fan is seeing the full 12-14 volts from the battery un-interupted because there is no resistor needed for high speed.
Now that you know why it breaks, let teach you how to fix it!
Step One: Buy a replacement resistor pack from your local toyota dealer or online. The dealer sells the part for about $35, and i have seen it as low as $10 online. I just went with the Toyota dealer, because they had one in stock and its only $35! Here is the new part.
Step Two: Look Underneath the passenger glove-box. Right up front you will see the Resistor pack, or at least the plastic part of it where the harness plugs in. Remove the Harness, Simply squeeze the connector and shimmy it outta there!
Step Three: Unscrew the two Phillips head screws that hold on the resistor pack. The bottom one can be accessed with a regular long screwdriver with the glove box closed. The top screw can be accessed two different ways. You can either use a 1/4 inch ratchet with a socketed Phillips head attachment, or you can open the glove-box and squeeze the inside of it to pull it down further and then you will be able to access the screw with the screwdriver! whew!!!!....that was a long run-on sentence!
Step Four: Remove the resistor pack by pulling it straight out, you might nedd to wiggle it a bit to get it out. (might come out in pieces from heat failure).
As you can see from the picture above, the metal pins are shot! one of them broke a solder and the whole ceramic heat sink is cracked and toasted!
Now, take a flashlight and look inside the cowling (hole that the resistor pack came out of) and make sure there is no debris in there! mine had quite a bit, so I vacuumed it out. I recommend you do the same.
Step Five: Reinstall the new resistor pack in the correct orientation. Be-careful, they can be quite delicate. If it breaks while putting it in, you'll have to buy a new one, because it will surly fail again if it looses some of its heat-sink. Don't forget to plug it back in!
Good Luck, Enjoy!
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