Dead AC/heater blower, 2000 Cherokee

Thanks, just what I needed. The relay was indeed blown with some visible scorching on 87 and 87a. Unfortunatly replacing the relay did not fix the problem. I tried the "relay circuit test" as outlined in the manual above but am a bit confused. It says there should be voltage to cavity 30 at all times, there is not. There is voltage to cavity 87 which the guide seems to say there should not be. Do I have a fried wire here?

Thanks,

Aaron

I'm getting closer to getting this thing fixed.

The blower itself works fine if I put a jumper across the main relay cavities. The relay itself tests out OK.

I found a blown 15A fuse, #25, in the fuse block. I replaced it but it blows as soon as the ignition is turned on. When I put a jumper across it the relay energized (I heard it click) and the blower worked properly.

Anyone know why this fuse would keep blowing out?

Thanks,

Aaron

Fuses blow to prevent the wires from melting and catching fire.

So, that means something down the line is pulling way too much current. That can be a motor that has shorted windings. Motors that fail this way still work but they draw a lot of current.

Disconnect the motor, put in a new fuse, and try again. If it doesn't blow it's the motor. If it blows then I dunno, need a schematic to help you any further.

#25, right above the two airbag fuses (only 2 that are labeled - Yes, I know there should be a label on the panel cover but there is not).

Thanks,

Aaron

OK, OK, my question was a little too general ;)

I just went out and pulled the relay which disconnects the motor as there is now an open circuit to it. The fuse still blew, instantly - at lest before I could get the meter on it - once I turned on the ignition.

-- Thanks,

Aaron

I have the basic factory radio w/cassette, it works fine. I have trouble believing it doesn't connect to the blower as the blower works properly if I use a plain wire to jump the #25 fuse socket. The #17 fuse, also 15A, cuts my radio out when pulled. Interestingly this fuse was also blown and replaced when this whole problem started, it's fine now though...

-- Aaron

Hi Bill, does not pulling out the relay effectively disconnect the motor since it receives its power through the relay? Perhaps I completely misunderstand this. I pulled the realy before I put a new fuse in btw, my writing may not have made that clear.

And time for me to look like a complete fool: What's a loom? (besides a thing to make fabric with).

-- Thanks,

Aaron

Yes, seperate fuse for the motor... fuse #6, 40A.

Your fuse #25 supplies power to:

1) Blower Motor Relay 2) Blend door actuator 3) Shift Lock Solenoid 4) Extended Idle Switch (Police Package) 5) A/C-Heater Control=20 6) Controller, Anti-Lock Brake 7) Controller, Anti-Lock Brake Relay (in PDC)

you can probably eliminate the Anti-lock=20 and the Police Package stuff. I'd start unplugging stuff and see which one lets it run... you'll need a good wiring manual for that, I'd spring for a manual, were I you. __ Steve . =20

Are you looking at the 2000 Cherokee FSM? On page 8W-10-1 the table of contents points to pg 8W-10-11 for Fuse 25(JB)... looking at Fuse

25 refers to diagrams 8W-12-20 and 8W-12-21.. the first one is left-hand-drive and the second one is right-hand-drive. Both the same for our concerns... they only differ in use of=20 junctions.

Fuse 25 in the PDC (Power Distro Center) is a different fuse... it does the Fog Lights. These are the ones under the hood, near the battery. __ Steve .