Kris4×4

Can anybody tell me where to find the blower motor relay on a 96 Jeep Cherokee? My wiring diagram doesn't show a relay but all the research I've done says there should be one and it should be behind the glove box. I've already got the dash unmounted and I can see what I think is a thermostat and an a/c relay, but no blower motor relay. I'm attaching a picture of my dash and schematic so you all know what I'm working with. Any ideas?

Kris4×4

Here's all the relays I could find. Does anybody have a diagram for the relay panel under the dash? I have a diagram for the PDC and don't see anything that relates.

Kris4×4

freegdr

Nothing under pdc lid ?

Kris4×4

No, here's my diagram for the PDC.

Kris4×4

I have searched all through this damn Jeep and I'm 100% sure there is no blower motor relay. I have a relatable question if anybody knows the answer. On the wiring harness that connects to the control panel, NOT the blower switch, how many of those wires should have 12V? It's got 4 connectors, 5 wires. There's 2 black/tan wires that I'm pretty sure head to the fuse panel. They both have 12V. There's 2 green/white wires in 1 connector. I believe 1 runs to the AC cycling switch and the other goes to something called AC signal select. Those wires have no voltage. And then there's a yellow/brown wire which I'm pretty sure is the same wire that eventually feeds through the blower switch and resistor (not sure though) and it has no voltage. I have a feeling it should have 12V. Is that correct? Been through all my diagrams and nothing shows that part of the panel.

moparado

On my 2K XJ, both the blower relay and resistor module are behind the glove box.
Very easy to gain access to.

From that generic Haynes schematic you posted, apparently the blower does not have a relay but instead what it calls a 'heater mode select switch' for some reason.

If you look at the Hayne's 97 and up year schematic, there's clearly a blower relay shown with its contacts and its energizing coil circuits.
That switch should IMO be a relay but according to the schematic, its a switch. Guessing its incorporated in the main 'A/C mode select switch'.

I keep hearing stories of connectors and wires burning up in the heater circuit, this could be the reason they switched to a real relay for 97 and up?

Whats needed is for someone here to post the real Chrysler schematic for a '96.

Have you located the blower motor resistor module?
If that switch is actually a relay which according to that schematic it isn't, it should be somewhere around the resistor module.

Only two possibilities, either there's no blower relay only a switch
or
that Hayne's schematic is faulty.

Since you can't find the relay, the odds are the schematic is accurate enough.

Kris4×4

That would make sense if they put a relay in later models cause I'm pretty sure I have a burnt up wire between my fuse panel and blower motor switch. I had just replaced the switch and resistor before I lost power. I decided to run a new line from an accy outlet in the panel. I put an inline 30 amp fuse and then spliced it, one way going to the switch, the other way going to the resistor. I got power back but then it would only blow on high. I checked the resistor that I had just purchased and I had zero continuity at the thermal fuse so I have to go buy another one of those. Hoping once I do that my problem is solved. Atleast I didn't pull my dash for nothing. Since I had to run a new line it should tuck nicely before I seal it back up.

I agree those diagrams in the Haynes manual aren't always worth the paper they're printed on. Been looking online to try and find an electrical manual but no luck yet. Starting to rain here so I'm gonna have to do the rest tomorrow. Appreciate all the help!

moparado

Sounds like you got a handle on it.
If it only blows on high then its getting power to the blower motor.

What a little puzzling is why there are two B+ paths to the blower switch and resistor module.
One feeding power from mode selector switch to the blower switch and the resistor module...
and the other path feeding power from the heater mode switch to the blower switch and the resistor module.
Only thing i can think of is they needed more copper for the high current draw from the blower though the schematic doesn't indicate when the heater mode switch is on.

I see now why they updated the 97+ XJs with a relay.

If the blower blows on high thats a good indication the blower and its connectors are ok.

It looks like a bad resistor module or its connector to me.
If that doesn't work then....
I'd check each and every connector involved for burnt or spread contact pins and follow any burnt wires to the culprit.
There's a better than good chance the connectors associated with any burnt wires are also toasted. Same goes for the involved switches.

Let us know once you get it all up and running.

Kris4×4

Finally got it all wired up and running. All four settings work. We recharged t
he AC and it was so cold it almost ran us out of the Jeep. It's a beautiful day!!! Thanks for all the help! And I found this wiring diagram in the process. Best one I've come across, and I've looked at many. Thought it might help someone else.

Jeep23

is there a relay or nah

awg

On a '96 and earlier, there is NO relay, its a very poor engineering design, as ALL current flows through every wire, including the ignition switch

to prevent burning up the ignition switch, I added FOUR relays, behind the kick panel, one for each resistor speed

On '97 and later they corrected this bad design

Jeep23

I can not find it on my 2000 jeep cherokee sport any idea or diagrams

awg

I doubt there is a relay on the later model, as the issue is the last point is 4 separate resistors for each speed,
so a relay is not effective
they changed the wiring or polarity in later models so all the current doesnt run through the ignition switch.

download the FSM that covers your model from Cruisers website for more detail

I did look at the wiring diagram for the later models, thats how come I know about the the issue, I think the later ones have a common earth, but cant remember exactly

Phreakism

If I may ask where exactly did you wire them in?
I've already changed everything once and my switch melted again, so this seems like the ideal solution.
Is it possible you could draw up a diagram?
I'm at my wits end with this melting wiring 😱