PETDOC

In a separate thread I've detailed my ongoing attempts at fixing a malfunctioning blower motor in my '88 4Runner (https://www.yotatech.com/forums/f116...tently-289370/). In short a new relay and blower motor didn't fix the problem. It appears it is a defective dash switch.
Can anyone tell me the approach to the dash switch? It appears I need to remove the top of the dash. If true any pointers on how to do this would be greatly appreciated.

wyoming9

iTrader: (1)

I need to look

You pull out the radio and the plastic around it.

to be able to access the control cables and the harness for the switch.

Being very careful the plastic clips get brittle with age

taking care to note where things go.

remove the cover plate then remove the 2 screws if you have AC the switch comes out the front.

Pull the heater control out the front.

You have checked the heater relay as that is what powers the switch??

I can see the resistor being shot maybe the motor you did test the motor??

PETDOC

Thanks for the advice. I had checked the old motor with a battery. It worked fine. Replaced old relay with new one, no change. Have not pulled the resistor, but will before going after switch.

Terrys87

iTrader: (1)

Getting to the switch can be a pain. Using this thread https://www.yotatech.com/forums/f116...4-88-a-278925/ is how I go about removing the controls. Even though it is on converting motors, the first few steps apply to it and showing the paint marks to getting the Cables back into their correct places.

I would check the blower resistor first before doing the switch assembly. Normally if the resistor is bad, it will work on the highest setting and none of the lower speed settings.

If the blower resistor is bad, pay attention to if it is the 3 prong or 4 prong resistor. It does make a difference and Toyota used both styles.

PETDOC

terry,
Thanks for the link. I now believe it is the resistor, but had discounted that based on how the blower motor had failed. Actually volt meter gave me insight that I failed to interpret correctly, i.e., zero voltage on lowest setting and 11.9 volts on 3 higher settings. Pulled resistor and it is fried.

bfmcelroy

https://www.yotatech.com/forums/f116...4-88-a-278925/


This is a little bit different than my '89 bare bones pickup. The dash is not the same around the radio/heater area. I don't have the "pocket" under the radio.


I need to do this as my blower motor only work at the 2 highest settings and only intermittently.

PETDOC

Bfmcelroy,
Thankfully my issue turned out to be a short inside the connector of the dash control switch and main wiring harness. The connection was on the right side of the center of the dash behind the glove box so disassembling the dash was not needed. On my unit once you separated the connector the short was obvious by virtue of a burned connection, i.e., it was black. After cutting out the connector and directly connecting all wires everything works fine.
My resistor was also blown, but that probably happened because of short in the control switch connector. Resistor problem was obvious based on visual inspection, wire coil was broken.