[girard]

:confused: hello, I need to replace an electrical blower fan switch on an old car. I can't find the same one as the car is old. The switch is a off, 1st speed, 2nd speed 3rd speed, high speed, sliding handle type switch. Its been going out for years and finally just won't work. I know the blower fan still works, as the fan switch when I leave it on sometimes comes on and blows, but often not the right speed. Or it doesn't come on and all. I've been told it could be other things, but I've a feeling it is the switch, as I've watched it going out for 2 years now or so. I don't care if I only have a new switch with off and on, and hook it up to the high speed contact. I'll find a way to mount it. The existing switch is fed by wires that are part of a plug. Once I figure out which ones need to hook up with one another for speeds or just the high speeds, do I then cut the wires, be rid of the plug and wire to the new switch. It would be nice to have the multiple speeds too, but if I cant, I can live with that.
Thank you, girard hall

[Stratmando]

Simplest would be single pole double throw, maintained with center off.
That would allow 2 speeds and off. Rotary switch may be more difficult to locate.
Power goes to center, and you pick the 2 speeds you want.

[girard]

Stratmando, would I need concern myself with resistors on the lower speed, well in fact on the higher speed too? Or are they built in to the switch? Also, how will I know it's a switch for 12 volt system, and is the amperage it will take safely a concern of mine?
Obviously I'm learning, thank you... girard

[Stratmando]

If you get the power from old switch, it is protected.
Sounds like individual wires to control speed. Insulate unused wires.
How many wires on switch?
The resistors may be at blower motor.

[girard]

Start, when I look at the back of the switch and consult my manual for this model car, I find the back of the switch has a plug coming into it. For various speeds and off and high, we find a continuity diagram showing which places in the plug should have continuity for each speed. Obviously I could just use say one of the lower speeds and high. Do I just clip the wires, put the ones in the new switch for a speed and also connect it to the other position shown for continuities sake. All of the speeds connect to a certain two postions, but the various speeds connect to other spots in the diagram too. I presume diff. spots have diff numbers of resistors.

[Stratmando]

You could put crimp on, push on terminals, with the insulating outer covering(No metal exposed). Then if you find slow is too slow, just unplug and plug in wire of desired speed.
Most Switches from auto parts, will handle a blower.
Your drawing, The continuity connections only connect hot to 1 wire at a time?

[girard]

Hello start, OK, I've found the exact switch I needed.(cost$67 dollars) and that wasn't the prob.! OK then I located(finally)the blower resistor. It is a part as you probably are aware that has several springs of different sizes on it. The part was all black, charred, and broken in two on one of the springs. I've been told that this part is about 30 dollars. I'm willing to pay for it as I've went this far. The beginning problem really anyway was locating the darn switch.I found this resistor mounted as you suggested it might be in the covering of the blower motor with it's springs in the stream of air for cooling I understand.
Now, since I've gone this far, I want to throw in a blower relay, and I've seen some drawings or schematics online of it, but I can't seem to locate it. It appears to be on the upper right side of the heater housing/casing but as I look I don't see anything or it doesn't seem to be on the outside, but then again I didn't see the blower resistor at first either. Can you be of any help on locating this relay, the car is a 92 toyota corolla and the heater blower motor assembly is behing the glove box on passenger side. I'm learning a lot and you've shed some good light, can you again help with the relay location?? thanks

[Stratmando]

I would look in the phone book, your area,"salvage yards", "Junk yards" you can probably find reasonable replacement.
Do you need blower motor relay?
Would be under hood with fuses and relays.

[girard]

No I have found the blower relay at the dealer. My problem is now the location on the car of the blower motor relay? What I need to know is it appears to be located under the glove or behind the glove boxup on the right side of the blower motor housing. I found the blower motor resistor over at the bottom on the left. I have illustrations indicating it appears to be under there somewhere also, but for the life of me I can't find a relay for it in that area. So you do t hink, in spite of what the illustrations indicate that it is under the h ood on one of the several fuse blocks? you've been a lot oh help on t his and I appreciate it. Thanks

[Stratmando]

I would follow the wires physically from blower, or from switch. Tone generator and inductive amp would be a great help. Have found the pair for $40-$50, on auction site.
If I can help, write back, let me know how you did. Take Care.

[girard]

Well alas I found the blower motor relay. It is beside and down from the assembly housing slightly. It was hidden behind kick panel material. It is on a fuse block which contains an a/c fuse, the relay, current breaker device I believe. I had been looking at it, but just thought it was some fuse with a different look. Finally I saw an illustration in my book that showed all the relay locations on the entire care, it was there and on the fuse thing, and looks like a square black box from looking down on it. A lot of relays probably look at it.
I'll put my resistor and relay on this weekend and let you know the outcome. Again, thanks and you'll probably see me again on here with some other problem, you know how older cars are!! thanks girard

[girard]

Well start, I'm back, suffice to say I've replaced the fan switch, the blower resistor, and the blower relay, and my fan won't blow. However odd thing is, sometime when I'm driving down the freeway, the fan does cut on at a low speed and run. Then the next time I start up it may be still running or most likely will have stopped again. I suspect the blower motor is OK, but maybe not after me replacing everything, I am flabbergasted.
At first, I felt certain it was the switch , then the blower resistor, then maybe the relay, and I've gotten nowhere. What would you do next?? I mean I am beat by this mystery, and this is the kind of luck I generally have too.

[girard]

Oh yes I forget, can you tell me how to do a shade tree mechanics test of the blower motor. i.e. with jumper wires I suppose. Is a jumper wire, just a direct wire connection between two points?

[Stratmando]

Service Manual with schematic good investment. They may have a Chiltons, Haynes , Clymer, or some manual on your car.
$5 Test Light very helpful, should have good power from fuse, fuse relay, blower switch, then to blower motor. Should be able to unplug at motor and apply ground and hot.
Jumping can be done at relay, switch or to motor.
If jumping directly from battery, Use 10-15 Amp fuse or DC circuit breaker protected jumper,
May have to make. Good Luck. If you could provide schematic, would be nice. Not Necessary.

[girard]

Strat:remember me?? Well Ive returned to beg for help again. Haha anyway, my toyota 92 corolla has been over the past 3 weeks been taking a bit longer and a bit longer each time I crank it , to get it to kick on over and start. It used to ALWAYS kick over in 3-4 seconds, I mean almost immediately. Now its 15 to 20 seconds and I fear its getting worse. It has a new battery. Wires and distributor cap and rotor and plugs replaced about a year ago.
Now it does and has for about 6 months had a slight miss when I first take off. It is only for a second or two and goes away. Or at least you can't feel it or hear it anymore.now if you're not careful why ou can get caught in this miss area when you first accelerate and have to let off and then accelerate or you will miss for a good bit.
I wonder if this miss is related. Should I get new wires, and dist cap and plugs and rotor again. I don't think the timing has slipped either. Anyway help if you can. GIRARD

[Harvey1955]

Have you checked all wires for good connections? Make sure all are plugged on solidly. Good luck

[Stratmando]

I also would check or replace plug wires, Remove distributor cap and check for moisture.

[CaptainRich]

A weak ignition coil can cause this type of misfire.

Primary circuit 1.1 - 1.7 ohms
Secondary circuit 9k - 15k ohms