Erratic blower motor operation?

Discussion in '80-Series Tech' started by Bushmaster6, Jul 9, 2010.

  1. Bushmaster6

    Bushmaster6

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    Newb. Lurked here for a long time, finally joined and searched but found no symptoms similar to mine, hoping someone has similar experience or advice.

    93 FZJ80. 227k miles. No owner's manual, no FSM, no Haynes.

    Everything worked fine until about a week ago I started getting strange action out of my blower motor:
    • blower or fan randomly works, regardless of which fan setting from low-2-3-high I have it set on
    • fresh air vs recirc switch works, but has no effect on whether blower motor runs or not
    • a/c compressor is working (cold air when the fan does blow and the engine is idling up when compressor engages
    • all lights on switch panel work
    • fuze appears normal, and again, I get (sometimes) full force fan
    • at the same time I started getting erratic blower motor operation, I started getting concurrent "static" in my (aftermarket) stereo which is commensurate with fan speed (sounds like static "ticking" at varying tempos coming through my speakers):meh:
    • performance is rarely all "on" or "off".. I get varying speeds/effectiveness as it runs, so.. as the fan is set on highest setting, I get fan perfromance from zero, to rising and falling medium speeds, and sometimes full force high
    Florida is hot in the summer time and schwetty ballz commute not so fun. Thanks in advance for any assitance.
     
  2. browardcruzer

    browardcruzer

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    94 FZJ80 here. The fan sounded like the bearing was going and made noises when I first got mine. Took the fan out and cleaned out the insulation, mouse nest, leaves and crap that had accumulated inside the fan. put it back together and it worked fine. still using the original.

    It is located under the dash on the passenger side. Poke your head under the dash below the glove box and it is pretty obvious where it is. Three small bolts and an electrical connection to get it out. it was fairly easy.

    I Would start there; if the motor is going, you can get it at Advance Auto for like $70
     
  3. Tools R Us

    Tools R Us

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    Sounds like the relay, IIRC it's marked heater relay? I had the same symptoms took it apart, cleaned the contacts with good results.
     
  4. kidglove13

    kidglove13

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    Had same type of issues.
    It was the relay located on top towards the back of the blower area up in the dash.
    It was a real bitch to get out.
    I cleaned off all the contacts and plugged it back in and stuffed it back in the dash where i could get at it easier if I need to later.
    The blower has been going strong since then.
     
  5. Bushmaster6

    Bushmaster6

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    thanks guys (two times)

    appreciate the feedback guys.. will start with relays and pulling the fan motor for a look-see at what's in there with it.. I just finished a hot and slow trip though alot of traffic leaving the annual Blue Angel's show on Pensacola Beach.. great show and worth the effort but, made for one tough ride home.

    I saw in other fan trouble shooting threads that the relay was in a kick panel on the DS floor.. kidglove shows it in vicinity of the blower motor.. guess I need to get exploring..

    appreciate mod that policed up my poorly worded attention grabber... :whoops:
     
  6. kidglove13

    kidglove13

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    There are 2 relays.
    One in the kick and one up in the dash above the blower.
     
  7. Bushmaster6

    Bushmaster6

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    relay location

    after ten minutes of exploration... more questions..

    appears to be two wires going to blower motor, both thick blue, but one with red stripe, other with yellow (I think, don't remember).. these lead to a white plug/connection, and further lead to (a) a split harness with two equaly shaped wires to those attached to the blower motor leading to a t-shaped plug, and (b) into a much thicker wiring harness which snakes up into the dash.. the t-shaped plug was not plugged into anything, and I don't see an empty hole for it to go to...?

    second question: on the DS kick panel is an array of four relays, three round metal ones and one square plastic.. pulled the one square plastic and the leads all looked clean enough, but unsure if it's gone bad... is this correct one?

    third question: behind the PS dash speaker is what appears to be a small ECU type computer device.. on the side are a ten wire connector and a five wire connector.. both of mine were unplugged.. not insinuating this has anything to do with my blower motor, but, do you know what they're for and should I plug back in?
     
  8. kidglove13

    kidglove13

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    I forgot what the relay behind the kick looks like it has been awhile.
    I think if you search there is apicture somewhere on mud.
    The wiring harness up by the blower and the empty plug I do not remember an empty plug up in the dash.
    The other wires that lead up into the dash beyond the plug go to the other relay which is a real PITA to get to.
    That is the relay that gave me problems.
    The box behind the PS speaker I think is the factory amp maybe.
    I will try and take alook behind my glove box to see what is going on in there if I get chance and report back tomorrow sometime.
     
  9. Bushmaster6

    Bushmaster6

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    relay location

    thanks KG. the help is appreciated.

    found this image on a mud search: http://forum.ih8mud.com/80-series-tech/251672-blower-under-dash-no-worky.html#post3864369

    that user's issue was resolved with a new ac control unit, which is (a) expensive and (b) probably a part I dont' have, as his was a climate control unit and mine is basic manual operation..

    so that explains the main relay in the kick panel (it's the square one), but that thread never gets to the relay behind the dash.. the only by name relay I found there was the 4wd system (I assume for the lockers) relay along the lower kick panel.

    stereo amp would make sense.. I have an aftermarket head unit so someone may have pulled that amp when it was installed.. plugged it in, turned teh key on, heard a noise in the speakers, and unplugged it again..
     
  10. Dave 2000

    Dave 2000 SILVER Star

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    The unit under the PS dash on my RHD UK model is the OE alarm system, not the most reliable system inthe world however it is getting on a bit now. Mine had been leaked on by the poor windscreen rubber sealing. I have posted you a couple of pics to help you ID the unit and plugs. If that is not the unit I apologise for wasting your time.

    regards

    Dave
    Resized alarm 1.jpg Resized alarm 2.JPG
     
  11. kidglove13

    kidglove13

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    That is not what he is refering to.
    Bushmaster: I checked out my rig.
    There is to much stuff for me to remove to get a picture of the other relay.
    Behind the glove box is the blower/condensing unit big black box.
    Unfortunately it is hard to remove that unit with out disconnecting the AC hardlines.
    I did not take it out which is why it is such a PITA to get to the other relay.
    Above that unit you will see the Engine Control Unit. Remove it.
    Also try and take out whatever other parts that will come right out.
    Once you get the ECU out the other relay is tucked way back above and behind the Blower/Condensor unit back in the dash.
    If you turn the power on in the rig and push the fan speed buttuns starting from medium up to high you should hear the relay clicking up in the dash.
    That is how I located it.
    Fair warning it was a real fawker to get to and take out.
    My climate controls are manual as well.
    Good luck.
    If you think it is the climate control unit itself you might be able to get one from
    cruiserparts.net
     

  12. Bushmaster6

    Bushmaster6

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    thanks KG

    thanks KidGlove.. saw the ECU when I was exploring yesterday so that's a good point of reference for me...

    yeah, nearly everything on the LC is a b-tch to get to compared to my CJs..

    --------------------- next question------------

    once I pull it, how do I "test" a relay? Do I pull it and run a multimeter to it uninstalled, or must it be connected to 12v at the time..?

    never mind.. found many links online
     
    Last edited: Jul 11, 2010
  13. kidglove13

    kidglove13

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    I could hear the relay clicking in the dash so I figured it was still getting some power.
    So I removed it and one of the plugs looked like it had melted a little bit and needed to be cleaned so I cleaned it up real good and plugged it back in a it all worked great.
    Maybe I got lucky who knows.
     
  14. Bushmaster6

    Bushmaster6

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    narrowing it down

    weeks later (had a biz trip in the meantime)...

    have the glove box out and have isolated the a/c amplifier, the ECU, the blowe resistor, and the engine coolant temp cut relay.. so I know what above and behind the evaporator unit is NOT the relay.. but still not sure what IS the relay...?

    is it the black box, approx the size of a deck of cards.. wiring harness come in from the driver's side, has 3 dimples in the plastic on the pass side, and appears to be mounted to the top of the evap housing? Item I'm talking about is mounted directly behind the right upper bolt that holds the evap housing to the dash..

    this item makes sense based on what KG described, but doesn't look like an automotive relay that I'm used to.. how did you get it out?

    if I've got the right part, I've been working on getting it out without breaking something sensitive.. taking a break now to avoid doing something stupid and hoping someone can lend some advice tonight or tomorrow AM
     
  15. kidglove13

    kidglove13

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    That little black box is the relay or what ever the tech term for it is.
    It is clipped in there somehow and I can't remember how but I had to really work it to get it out not much room and a reall PITA.
    Once I got it out I did not put it back in the original spot I just stuffed it up in the dash incase I had to get to it again.
    With the key on and you press the fan speed buttons can you hear it clicking?
    It should beable to hear it click when you press the buttons.
    And yes it is about the size of a deck of cards.
     
  16. Bushmaster6

    Bushmaster6

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    thanks KG

    I'll try the switches when I re-attach the battery this morning..
     
  17. 96r50

    96r50

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    This one?
    [​IMG]

    It's there in my truck too, and I'm not sure what it is for :meh:
     
  18. Bushmaster6

    Bushmaster6

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    victory

    ended up buying a replacement relay (it's called something like Cooling System Relay in the factory parts search).. cost me 77 bucks at the local stealership, and I had to go down there face to face to explain to the guy what it was and where it was located to get the right part.. but it was available next day so, shipping overnight from other, cheaper places would've probably put my cost nearly that high anyway..

    it was a bit of a pain to pull out, and I finally decided to snap it loose (broke a piece of the hold-down mount that's been replaced by the new part).. the FSM would likely tell you to evac the refrigerant and drop the evaporator, but you can get to it without doing so, just have to do some Houdini hand moves to get at it...

    unlike the experience of others here on mud, I didn't have fixable corrosion or leads, this part looked nearly new when I pulled it out, it had just failed over time, so a replacement was required.

    thanks KG for the technical advice and quick responses.. saved me some money and a long hot roadrtip to TX this weekend:beer:

    If anyone needs a pic or the part number let me know and I'll send what's on the dealer receipt.
     
  19. kidglove13

    kidglove13

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    So I assume that it all works fine now?
    If so congrats and enjoy your AC.
    That thing is a real PITA to get at.

    If you could post up the part number that would be great, you never know.
    I know mine is on borrowed time, at least that is what I thought over a year ago.
     
  20. Bushmaster6

    Bushmaster6

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    part number

    just drove 1200 miles in 4 days (Pensacola to Dallas and back) and the truck did great.. even with 105 degree temps in Dallas area, had to mix the warm/cold in my vents to keep it from being "too cold"..

    my receipt gives part number
    88630-20020, "Relay Assy"

    when we researched it on the computer based parts catalog at the dealer, the item was title "cooling system relay" (or something similar, but the word "cooling" was definitely in there to distinguish it from other relays).. 77.21 at my local dealer, plus tax

    cheers
     

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