98 zj heater blower issues?

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[bigdaddee]

i was told there is a relay switch or something between my fan speed control switch and the blower motor itself on my 1998 grand cherokee laredo. its the 4.0l if it matters. got heat but no fan speeds. new blower motor and entire heater controls switches installed but? someone knows. Spill the beans and help me out if u can



thanks
bigD

[Posimoto]

No relay switch.

First, check the connecter plug, sometimes they burn out. Second, check the motor followed by the resister, and finally the switch.

The wire coming from the motor should lead to the resister just follow it. Should be mounted to the heater box by 2 screws.

http://www.factorychryslerparts.com/images/parts/Chrysler/fullsize/0000098A.jpg

Edit: #14 is the resister.

[Crown Automotive - Jeff]

http://www.crownautomotive.net/mm5/merchant.mvc?Screen=PROD&Store_Code=CA&Product_Code=4720278&Category_Code=  Rich, if you need the resistor, we carry them.

[Krome]

need a blower motor? I got one

[bigdaddee]

Ok back to this issue as it has yet to be resolved just didn't need heat and never used air over the summer.
Issue im having to recap:
I have hot air trickling out of the system so the degroster will alowly defrost my window after a while but i have no fan running at any speed. Not being good at diagnosing i have replaced the following parts:
The in line resistor ( thanks jeff@ crown)
The 3 switch cluster on the dashboard.
( it's one unit)
Now I have tested with just a simple tester light and seem to have power( enough to light the les tester light) to the terminals on the switch, the blower motor itself even when the fan and heater switch is in the off position. Odd!


I need heat damn it. Anyone know an easy way to diagnose this and get me some heat?  Willing to pay you. Just figure this out for me because it driving me up a freaking wall. I will buy u a case of beer or a case of milk I don't care just get me warm lol

[SPYDER]

have you tried jumping the fan off the batter, to simply rule it out of equation??

[BlackKnight]

Had this happen to my Wife's Grand Cherokee just 3 weeks ago. There is a resistor on/near the connection to the blower that in my case fully melted/disintergrated. I had to have it replaced and cost me 200$ as I don't yet have the know how to do it myself, and requires removing the entire dash unit to get access to the blower

PS> Now that I finished typing I noticed you replaced the line resistor, so now your beyone my experiance, other than the blower itself...

[bigdaddee]

Yeah your wife must have a newer grand Cherokee? My resistor was easily accessible and I replaced it. I hear these are culprits most of the time or the wiring gets corroded or burn up. All looks good and yes Spyder I jumped the fAm and it works perfectly fine. Though. About just hot wiring to its own switch but I hate doing things like that half asses. Rather fix it right



Someone come fix this or I will bring u my jeep and whatever it is you love whether it be booze or a box of chocolates lol

[BlackKnight]

Yeah your wife must have a newer grand Cherokee? My resistor was easily accessible and I replaced it. I hear these are culprits most of the time or the wiring gets corroded or burn up. All looks good and yes Spyder I jumped the fAm and it works perfectly fine. Though. About just hot wiring to its own switch but I hate doing things like that half asses. Rather fix it right



Someone come fix this or I will bring u my jeep and whatever it is you love whether it be booze or a box of chocolates lol

Yep, a 2k Gr Cherokee... Second time I had to get the dash pulled apart... Aparently the AC is a known issue, as the condensation sits at the bottom of the condenser core and rots it out. it was replaced 3 years ago

I'm wondering if the Hotwire to the battery worked, maybe it's the switch that is the issue. Do you have Climate control? or just the manual adjust?

[SPYDER]

blackknight...you got raped.  there is no reason to remove the dash for the resistor...its bolted to the front of the hearter box...if anything has to be removed its just the glove box door.  its a very common repair so they make it easy to get out...the other issues you had years ago, i can't speak of, but the only time in my 7 years of a tech that i removed a dash in a gc was to replace the blend-doors in the hvac housing.


bigdadee....are your hvac controls vacum actuated?  and just for kicks have you checked fuses?

[BlackKnight]

blackknight...you got raped.  there is no reason to remove the dash for the resistor...its bolted to the front of the hearter box...if anything has to be removed its just the glove box door.  its a very common repair so they make it easy to get out...the other issues you had years ago, i can't speak of, but the only time in my 7 years of a tech that i removed a dash in a gc was to replace the blend-doors in the hvac housing.


bigdadee....are your hvac controls vacum actuated?  and just for kicks have you checked fuses?

Wish I knew that a couple weeks ago

[bigdaddee]

Yes spider I checked all fuses inside and under the hood all are good. Yes I have the vacuum control but I can hear it change positions and that system is working up to par as is the hot to cold dial and the ac button. Just the circuit the fans on is an issues but as I said I jumped the fan and it worked fine. thaws hoping not to have to buy a voltmeter as the one I have capped out. Plus I'm no expert at using them but it may be my only option.

Maybe I should make the yj a daily driver and wheel this pos!
Actually I would want heat regardless it's winter

[Posimoto]

If what you mentioned is accurate, new working switch, new working resister, and working blower motor it can only be one thing you have an open circuit on the power side circuit.

Start at one end and work your way down line until you find the open.


 

[SPYDER]

posi...it could be a bad ground....but it sounds like you are correct.  id borrow a volt meter or buy a cheaper one and chech the circuit.  or just simply fall the wiring as best as possible.

[BlackKnight]

posi...it could be a bad ground....but it sounds like you are correct.  id borrow a volt meter or buy a cheaper one and chech the circuit.  or just simply fall the wiring as best as possible.

I'd have to dig for it, but I think I have one you can borrow. Where do you live? where can me meet for me to drop it off if I can find it? (I'll dig for it tonight after work and reply back if I can find it.)