SmashedGlass Posted April 16, 2014 Share Posted April 16, 2014 When I bought my '88 GL wagon, it didn't take long for me to find out that there was an issue with my HVAC blower not operating on all of it's speeds. Replaced the resistor pack in the blower housing, but also discovered that my fan speed control switch had a partially melted connector to the main harness inside the dash. The culprit, in this first case, was the solid blue wire which I believe is the main power supply wire. Anyhow, I managed to "repair" the connector by cutting the melted in spades free of the plastic and then moving the spades on both sides of the connector to the one unused slot in it (5-wire switch, 6-wire connector...go figure?). Fast forward to the last month or so where I had to tear the entire car apart due to a rain water leak into the passenger compartment. That blue wire got a little hot again, not enough to melt and blob up the connector like it was but enough to shift the spades in the connector. And, I managed to pull the wire out of the female spade to add insult to injury. So, I contacted another board member about a car he was parting out and he sent me a complete speed switch with connector and plenty of main harness side wire still connected to it so that I could cut my old connector out and solder in a good one........Or so was the hope. The switch and connector sent to me, had suffered the same fate that mine originally had, the same (solid blue) wire melting the connector to the point that it had to be coerced with a knife and mini-saw to get it apart. And possibly this time the main ground wire (black) also had gotten heated up enough to melt a bit. I managed to effect the same style of repair as last time on the new connector by hacking out the melted spades and moving them to the empty slot, but...........HERE'S THE QUESTION...... Is this an inherent fault with the blower motor switch set up on the 3d gen GL and Loyale? Kind of odd that both switch connectors suffered the same damage. My wiring schematic (which is not from an FSM, but the Mitchell books are pretty close to an FSM) shows FIVE positions inside the switch, with one labeled "Off" but as anyone who owns one of these cars knows the switch knob has no "Off" on it's label, only 1-2-3-4, and the knob itself of course only sits in four different positions. Is the switch always receiving power then, and eventually overheating from always having power running through it? I am concerned about putting my dash back together and then later on down the road possibly having a fire under my dash. Seriously...... Link to comment Share on other sites More sharing options...
TallonX Posted April 16, 2014 Share Posted April 16, 2014 Power to the switch should be killed when you press off on the heater control panel Link to comment Share on other sites More sharing options...
l75eya Posted April 16, 2014 Share Posted April 16, 2014 Is "1" actually a fan speed? In both of my cars, the fan doesn't function until I move that selector to "2". Link to comment Share on other sites More sharing options...
SmashedGlass Posted April 16, 2014 Author Share Posted April 16, 2014 That's exactly what I thought, but I'm thinking now that unless you press in the 'off' on the mode panel, the switch is still powered and building up heat. All. Damn. Day. Link to comment Share on other sites More sharing options...
ruparts Posted April 17, 2014 Share Posted April 17, 2014 hi, if the mode switch is in "any" position other than off, the fan circuit is receiving power to run the fan, and the fan should be running at whatever speed it's switch is set on. the resistor can have 1 or more bad speeds, but the circuit is powered. if the blower motor is drawing excessive load to run it, (like a tight bearing or debris in the fan, etc.) it will heat the wires. also a bad ground somewhere in the circuit can cause extra heat in the connections. Link to comment Share on other sites More sharing options...
rrgrr Posted April 17, 2014 Share Posted April 17, 2014 My off switch doesn't work -it diverts the air to the dash somehow. The fan resistor is shot but works on 3 & 4. Haven't been able to get the old one out yet, one of the screws is all rusty. Is "off" a function of the resistor pack, or the switches, or some combination? Link to comment Share on other sites More sharing options...
ruparts Posted April 17, 2014 Share Posted April 17, 2014 My off switch doesn't work -it diverts the air to the dash somehow. The fan resistor is shot but works on 3 & 4. Haven't been able to get the old one out yet, one of the screws is all rusty. Is "off" a function of the resistor pack, or the switches, or some combination? Hi, this was someone elses thread but in the interest of overall information,, the off position on the mode switch, and all the various modes,, is more/less a function of directing vacuum to various flapper doors in the system,, it does have an electrical switch component to it, "off" , is supposed to turn off the power to the blower fan circuit, the resistors are farther downline. any position except off on the mode switch is supposed to allow power to the blower circuit, and, direct vacuum to move the air doors to allow that selection. if the any doors are stuck or a bad vac actuator then there will be problems with air flow getting where it should. Link to comment Share on other sites More sharing options...
l75eya Posted April 17, 2014 Share Posted April 17, 2014 hi, if the mode switch is in "any" position other than off, the fan circuit is receiving power to run the fan, and the fan should be running at whatever speed it's switch is set on. the resistor can have 1 or more bad speeds, but the circuit is powered. if the blower motor is drawing excessive load to run it, (like a tight bearing or debris in the fan, etc.) it will heat the wires. also a bad ground somewhere in the circuit can cause extra heat in the connections. So with the push buttons anywhere but in the off position, with my fan selection on 1 my blower should be running.. Got it. Both my cars have no blower action at 1, I guess both have gone over the years. 1 Link to comment Share on other sites More sharing options...
SmashedGlass Posted April 17, 2014 Author Share Posted April 17, 2014 Or it is running so faintly that you don't notice it....Like I said, there are four speed positions on the knob and #1 is apparently not "off". Link to comment Share on other sites More sharing options...
rdweninger Posted April 17, 2014 Share Posted April 17, 2014 Most of the time, 1 and 2 get fried in the resistor pack... because of the constant flow (resistance) thru the pack. Most people did not push the 'Off' switch. They left it on 1 or 2. Here is what I do... I leave the setting to 4. Therefore, the full 12 volts makes it to the fan. No electricity runs thru the resistors. When I'm happy with the heat or defrost results, I turn the unit "Off'. All 4 of my settings work... I'm just preserving the resistor pack. Same reason I don't use my brakes.... Ha! Link to comment Share on other sites More sharing options...
nipper Posted April 18, 2014 Share Posted April 18, 2014 If your resistor pack is working, you may want to pull it out and gently clean it. Since it is in the airstream in the HVAC box, the coils can collect dirt and cause them to overheat. Link to comment Share on other sites More sharing options...
WoodsWagon Posted April 19, 2014 Share Posted April 19, 2014 A melting connector is either a connection issue or an overload issue. Low spring tension of the female side spade connector or corrosion on their surfaces raises the resistance of the connection. If it was a perfect connection there would be no heat generated. It should take some effort to push the spades together or pull them apart, if not squishing the female side with pliers a bit while it's apart can tighten up the pin fit. The other option is the fan motor drawing more amps than the circuit was designed to handle. The oil in the bearings of a 20 year old motor probably isn't the greatest so it may be working harder than intended. The radiator fans in my dads 300k+ mile legacy were drawing 36amps and 24 amps each vs 12amps each for the same fans in our 200k mile parts car. The excessive load had cracked a fuse so they would only run intermittently. Link to comment Share on other sites More sharing options...
SmashedGlass Posted April 19, 2014 Author Share Posted April 19, 2014 Small update on the situation: my friend who has access to a Subaru-rich parts yard environment has gone back and gotten me another connector, one which is good. But here's the rub: he went through pulling THREE (or more) of them on this trip in order to find ONE that was not burnt. It occurs far too often IMO to not be some sort of faulty design in the system. Link to comment Share on other sites More sharing options...
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