Blower speeds 1,2,3 inoperative
#46
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Originally Posted by Ron_H
Dave A and I have already skinned our knuckles trying to replace the original with the one that's in there. Now I need to replace it also, I suppose, with a new one. I have all three blower speeds. Just this irritating high speed intermittant "on" that happens in town. Anyone ever get this gremlin??
Using a screw and string I got mine out and back in with no skinned knuckles in a few minutes. It is likely that the resistor pack is the problem. Maybe we'll have a resistor pack day.
#47
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AFAIK, you could do it to your '88, the GTS is wired differently, however.
This is the after pic. The lower left terminal has been removed to stop the crazy blower. The red w/white stripe wire has been moved from the lower row to an empty socket above it, to disable fan speed zero.
![](https://members.rennlist.com/porken/MagicBlowerFix2.jpg)
I'd like to know if someone has successfully stopped the resistor pack problems with a new blower?
Originally Posted by Charley B
Am I correct in concluding that I can eliminate 'magic blower' and stop 0 fan speed by removing the lower right recepticle and moving the red wire and recepticle to the hole opposite its current position?
![](https://members.rennlist.com/porken/MagicBlowerFix2.jpg)
I'd like to know if someone has successfully stopped the resistor pack problems with a new blower?
#48
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Thanks Ken, I'll give it a try on the '88. The blower comes on if the car is sitting there with no key in the ignition and the vent slider control lever in any position but far left.
#49
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Originally Posted by Charley B
Thanks Ken, I'll give it a try on the '88. The blower comes on if the car is sitting there with no key in the ignition and the vent slider control lever in any position but far left.
Classic magic blower syndrome......no biggie if it works normally the rest of the time! I've noticed it does seem to be worse in the summer....(which makes sense)
#50
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Treat the cause, not just the symptoms. A loss of air flow across the resistor pack can lead to resistor pack overheating or failure.
Most overlook this and replace the resistor pack, without cleaning the evaporator fins.
Here's a PWM motor speed controller that could be modified to work with the existing HVAC fan speed **** (fixed resistors instead of potentiometer).
http://www.electronickits.com/kit/co...tor/ck1400.htm
The PWM controller is much more efficient, so it wouldn't need to be in the path of the air flow.
Most overlook this and replace the resistor pack, without cleaning the evaporator fins.
Here's a PWM motor speed controller that could be modified to work with the existing HVAC fan speed **** (fixed resistors instead of potentiometer).
http://www.electronickits.com/kit/co...tor/ck1400.htm
The PWM controller is much more efficient, so it wouldn't need to be in the path of the air flow.
#52
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Ken, that looks like a great temporary fix, but I'd be worried about an overheat condition melting the HVAC duct. Personally I would prefer that my fan either come on full or stop if it's getting too hot, so that I know it needs investigating. If I lived in a wetter climate where the defroster is essential, I would prefer the early style.
Ron, it may be that your fan is drawing too much current -- maybe it needs a shot of lube. I seem to recall that the one we put in there was used, but if it was new I'd definitely look to the fan or the evaporator as borland suggests.
Charley, the blower should never come on without the key. Maybe your defrost relay is acting up or it's coil circuit is shorted to something else that has +12v with the key off.
I think that the early or late resistor pack could be used on early or late cars, so long as the wiring is adjusted to suit the function of the part in use.
Ron, it may be that your fan is drawing too much current -- maybe it needs a shot of lube. I seem to recall that the one we put in there was used, but if it was new I'd definitely look to the fan or the evaporator as borland suggests.
Charley, the blower should never come on without the key. Maybe your defrost relay is acting up or it's coil circuit is shorted to something else that has +12v with the key off.
I think that the early or late resistor pack could be used on early or late cars, so long as the wiring is adjusted to suit the function of the part in use.
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Originally Posted by SharkSkin
Early is NO, late is NC.
However, according to your earlier reply, I would have to adjust the wiring going from early pack to later.
It would seem to me that if this were a running change in 89, there would have to be a VIN number breakpoint if the harness plug is wired differently. I guess there is more to this puzzle.
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Looking over this again, according to the PET PN, I have an early style pack, but everything else indicates it is late style. See upside down sticker on part with (92)8 618 101 01. But design matches later as indicated in the Tech Service Info.
Last edited by Bill Ball; 12-28-2006 at 03:21 PM.
#55
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For what it's worth I had the same problem and I purchased the new pack only to find that emery cloth on the contacts resolved the problem. Mine looks like the new design and I have still have the new one if anyone ever needs it.
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"The blower comes on if the car is sitting there with no key in the ignition and the vent slider control lever in any position but far left."
Not normal operation, not "magic blower syndrome". This is a totally different can of worms, and almost certainly has nothing to do with the resistor pack. The blower circuit should have no power except when the ignition switch is on.
Not normal operation, not "magic blower syndrome". This is a totally different can of worms, and almost certainly has nothing to do with the resistor pack. The blower circuit should have no power except when the ignition switch is on.
#57
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Originally Posted by Bill Ball
Strange again, because my resistor pack has the early PN and the fan now works normally again with the contact soldered closed - a temporary fix. New LATE pack arriving tomorrow - THANKS TO ROGER.
However, according to your earlier reply, I would have to adjust the wiring going from early pack to later.
It would seem to me that if this were a running change in 89, there would have to be a VIN number breakpoint if the harness plug is wired differently. I guess there is more to this puzzle.
However, according to your earlier reply, I would have to adjust the wiring going from early pack to later.
It would seem to me that if this were a running change in 89, there would have to be a VIN number breakpoint if the harness plug is wired differently. I guess there is more to this puzzle.
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I reinstalled the old pack with the contact soldered closed (I could not get the contact arm bent back so the points would make contact). Fan worked as it should, but I noticed a distinct burning smell within less than a minute. Maybe some oils from handling burning off. Whatever. I didn't wait to see if it would disipate or do something nasty. I unplugged it and will wait for the replacement from Roger to arrive.
#59
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Could be oils from handling, or solder flux dripped on the resistor(s). Try plugging the replacement in without mounting in place, keep it cool while testing with a heat gun set to blow cold air. I'd expect the wires to get a tad warm while operating, but not so much that it's uncomfortable to hold onto them. If they do get warm, I'd suggest cleaning/lubing the fan.
I wouldn't go by the pic to determine early vs late. They may have redesigned both parts to use a thermo-switch(NO or NC as appropriate) rather than a bi-metal strip. You should be able to verify correct 89+ operation on the replacement by checking to see if pins 6 & 8 are shorted together when cold -- they should be connected together by the thermo-switch.
I wouldn't go by the pic to determine early vs late. They may have redesigned both parts to use a thermo-switch(NO or NC as appropriate) rather than a bi-metal strip. You should be able to verify correct 89+ operation on the replacement by checking to see if pins 6 & 8 are shorted together when cold -- they should be connected together by the thermo-switch.
#60
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Bill,
I would double check the wiring diagrams to see if the wires need to be rearranged in the
connector. I seem to recall that the two versions were slightly different.
I would double check the wiring diagrams to see if the wires need to be rearranged in the
connector. I seem to recall that the two versions were slightly different.