The blower motor resistor pack-fixable?

Discussion in 'Electronics' started by Karlosfandango, Feb 15, 2014.

  1. Karlosfandango

    Karlosfandango New Member

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    Mine just decided to die in the space of 2 hours. I removed the blower motor as there was a really annoying rattle when running on speed 2. Sorted that, put it all together, tested it and all was well. 2 hours later it now only works on 4:flame:

    As i'm in the UK the part is $50-60!!!!!! I'm thinking if I can find what the resistance values are across the contacts then i should be able to solder something in place to mimick the current set up.

    I have a workshop manual that has wiring diagrams but unfortunately no mention of resistance values. Is this info available at all?
     
  2. Ohio-white-kj

    Ohio-white-kj Full Access Member

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    Tough luck - I doubt the numbers are available. Maybe someone has one laying around and could check with a VOM. Also - it's one of those things that would not need to be precise. You could check about any pack from another vehicle and get some slower speeds.

    I'm sure one could calculate it also, but it's beyond my skill level. :wave:
     
  3. Karlosfandango

    Karlosfandango New Member

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    I tried but failed. I stripped the resistor (credit card) away from the plug and did a bit of tinkering. There are 5 contacts. 1+2 are a constant feed so when you set the fan speed dial to 4 it comes on at full whack.

    The slower speeds are achieved by sending the current on longer and longer tracks around the board. Contact 1+3= fan 3, contact 1+4= fan 2, contact 1+5=fan 1. I tried to measure the resistance across each section of circuit and thought I'd come up with each one being around 5 ohm. So fan speed 1 has 15 ohm resistance, speed 2 has 10 ohm resistance and 3 has 5 ohm resistance. When I soldered some resistors in place only speed 4 worked and the others just made the resistors start to smoke!

    Must be a different kind of resistor maybe? I even tried to half the resistance on each section but the same happened. Looks like I've got to suck it up and buy a new one.
     
  4. Snail Farmer

    Snail Farmer Full Access Member

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    Do some searching on here.. I've never had to replace mine but I've heard that others have used the resistor from a Sebring I believe. Supposed to be more stout and might be easier to get ahold of. Good luck either way.

    Sent from my HTC One using the power of Mary's purse
     
  5. jake1234

    jake1234 Full Access Member

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    I've seen pictures of the Sebring's board, it has an aluminum heat sink on it which makes it a difficult fit. I had some trouble swapping mine out with the one meant for the Jeep due to the tight space
     
  6. Jcdes

    Jcdes Full Access Member

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    I know this is a very old thread but just to add some info, there are no resistors in there (at least not the way you would think) resistance is achieved by joining all terminals with traces of different length and thickness. I replaced mine and just for fun removed the black coating and exposed the pcb. There was a lot of corrosion on the pcb so the following diagram might not be accurate but will serve as an idea as how this thing is designed.
    05 Liberty Resistor Block.png
     
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  7. LibertyTC

    LibertyTC Well-Known Member Staff Member Moderator

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  8. Billwill

    Billwill Full Access Member

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    That is a common way of creating "resistors" on a circuit board instead of soldering real resistors into place.....those are "resistive" tracks...not copper.

    My old Export CRD 2002 resistor board is working just fine so I do not want touch it but can anybody tell me please what the actual resistance should be from point to point! Replacement components are very expensive here in SA so if I can repair a blown resistor track with an off-the-shelf resistor it would help! The Sebring was never sold here so the more-robust pack from that vehicle is not available here!:(