Heater Fan Variable Speed Switch - Resistor Rating

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Joined: Mon Aug 01, 2011 2:18 pm
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Heater Fan Variable Speed Switch - Resistor Rating

Post by sideshowbob »

I am aware that the variable speed rotary switch controls both the fan speed on both the A/C and heater cycles.

At present the variable speed rotary switch works as it should on the A/C cycle.

On the heating cycle it only works on maximum. From previous posts this leads me to believe that the transistor on the small control module situated behind the fan on the air intake has failed.

I have removed this unit and unsoldered the old transistor (2N3055) and aim to replace it with an uprated unit (2N3771) as suggested on this site.

My problem is while unsoldering all the components I have lost the resistor that is soldered across the two terminals on the transistor.

Could somebody please advise the rating of this resistor ( from memory the body is light brown with red and black indicator rings)

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Re: Heater Fan Variable Speed Switch - Resistor Rating

Post by wattsmonkey »

Wow - tidy shed makes finding bits easier - I found a replacement heater valve with a good diaphragm too!
blower transistor reverse.jpg
blower transistor reverse.jpg (76.54 KiB) Viewed 43 times
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
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