skipp42

"88" Pioneer has been doing great til the temp outside hit minus 0.
Went to take the wife to Walmart in the jeep since we had snow and ice on the streets and the little Pioneer does great on both. Fired it up the set the heater on defrost and turned the switch to high, heard a noise that reminded me of a bearing trying to seize, just a quick sound and then nothing. blower won't blow air. I figure the blower motor went and will have to be replaced. warmed up a bit today so decided to fix the darn thing. As i have learned here, don't just go buy a part til your sure what it is and you have to have it LOL. So, before I pulled it all the way out decided to test it to make sure it's the motor and not some other issue. I have a couple of jumper leads 6' long with tiny gator clips on each end made up just for this jeep. hooked it up and the motor pops right off running like a new motor, no noised and turning like a jet turbine. problem had to be elsewhere. Check the fuse, shoulda been the first thing dummy. Fuse looks funny so try to get it out, won't budge, put a small set of pliers on it and yanked straight back, what i get sends chills down my spine. (1/2) half of a fuse burnt like it was hit with an arc welder and the other half is welded in the fuse box. I don't recon what caused it matters at this point, the bigger issue now is how difficult is it to replace that fuse box? or how to bypass it? Being a jeep I'll bet there isn't one inch of extra wires on the damn thing so I can get to the back of it ????

CCKen

Fascinating.

Radi

Check the blower motor resistor pack, a short there is a common cause of that fuse blowing.
No point in wiring around the fuse box until you find the cause of the failure, the new wiring will fail too.

skipp42

Hi Radi, totally agree with your assessment. Got half the dash off but can not figure out how to remove that glove box. I have removed all screws I can see but the box won't budge. Any suggestions would be appreciated. Thanks.

firehawk618

Manual trans?

My 89 had brake fluid leaking onto the fuse box for what appeared to be a long time *previous owner jerry rigged EVERYTHING* and basically destroyed the fuse box.

I ended up grabbing a mint one a a JY, pulling my box down from under the dash and spliced a new one in.

No fun BUT everything works now.

My fuses were all either brittle, melted or just plain welded in due to the brake fluid leaking on it for years.

*FYI* Not making one giourmous string of sentences makes it MUCH easier to read in a forum.

DFlintstone

Ha! You beat me to it firehawk. Skip, when the clutch master cyl. goes, it will literally **** brake fluid right out of the fuse-box. So there IS that to add to the equation. Then maybe we are wasting our time because we don't know what you have.

Parsnip

Assuming the least amount of things here, one of two things has happened.

1) when blower motors get old and the brushes that drive them get worn, they start taking more power to turn them, my old one would eat 20a fuses till I replaced it.

2) the resistor is dead, another common thing that will fail.

When using your test leads, did either get very hot?

skipp42

Howdy Don, It's an "88" Pioneer 4x4, 5 speed manual, 4.0 L w/o air. No oil or any other liquids present on the fuse box or firewall either side. I'm guessing but the blower motor is probably an original from 1988. I jumped the motor directly from the battery via the connection behind the firewall in the motor compartment. I responded instantly and spun like a top. I checked to see if there was any wobble of the squirrel cage, there was none. I spun it by hand to see if there was drag on it and it spun easily. Doesn't mean that the Armature or windings aren't going bad. It's been suggested that jeeps have had known problems with the blower resistor but I don't know how to get to it. The lower half of the dash is off, the trim around the glove box is off, all the screws that I can see that would hold the box in are out yet I can't budge it, it's like there is another anchor firmly holding it in place. My understanding is that the resistor is directly behind the glove box. Am I missing something that would be holding the box?

Larry's XJ

DFlintstone

Hey Skip. I remember now... If I've had my glovebox out, I don't remember. I looked at the 88 FSM, found about nothing except the wires to the resistor may well be, Lt BLU, Lt Grn, Tan, and ORG-t. I did though find for the 90, you go at it from underneath it looks. (see picture). So...you don't know if at some point that 88 didn't leak brake fluid into it's fuse box. Not to disagree with Radi, (or anyone), but I'd take a shot at fishing that stub out of the fuse-box and trying another fuse. You just might get lucky if you give it a chance!

skipp42

We must be psyced together Don LOL. I kept at that leg of the fuse and 2.5 hours later I finally got it all out. Had the battery disconnected so put a new fuse in to see if it would go in right and it did.

Update for the forum!!! I know where the darn resistor is on an "88" for sure, don't know about the rest of the group of "88 to 93" but the "88" isn't behind the glove box. It's located directly BELOW the glove box, mounted at a 45 degree angle on the lower portion of the blower box (plastic). It has a half rounded plastic cover over it that has two screws to hold it in place. I saw the damn thing before I tore my dash completely apart but didn't think that was it due to some A-hole stating it was behind the glove box and that the box needed to be removed to get to it.

I have something for that clown . lol.

I don't see a thing wrong with this resistor but there is a diode (?) mounted where the hot lead comes in and I can't read it so afraid to put juice to it least I blow the diode if by chance it's not already. The resistor is only 22 bucks so i think I'll get it and try the heater. The wires that I can see all look good, no melting or scorching and not to brittle. I will update the results to the forum.

skipp42

"UPDATE" Wonderful, I have heat once again. It was the heater blower motor after all. After checking the resistor for any shorts or the diode being bad I reinstalled it, installed the new blower motor then hooked up battery. I made sure the the heater was off then installed the new fuse. Reached in and started the car then got down where I could see the fuse box and fuses just in case then reached over and turned on the heater. It worked just like new. All functions work as they should and I have twice the air flow as the old blower was putting out. Should anyone need to replace or check their blower motor resister it can be reached without removing the dash. it's covered by a rounded plastic cover that has one screw located to the top left of the cover and one screw behind and just to the right that goes straight upward. once the cover is removed you can see the connector, remove that and take out the two phiillips head screws and the resistor pulls straight out. this is on a 1988 Cherokee but may be the same on "89 to 93's" as well, but a quick look will let you know.
Thanks guys, as usual I find this forum to have a great membership of well informed and very helpful folks. so glad I became a member.

DFlintstone

Glad that fuse-box didn't blowup in your face! Glad you got it!