How is this for strange??

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jeepguy4276

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OK the 2002 KJ uses only a PCI bus which most code readers will not be able to read so do not plug any code reader in to the communication port as it will only make matters worse.

When you have so many problems it is best to start with the easiest problem ie. the blower motor not working....no Bus involved here!

Download the 2002 KJ Service manual and go to section 8W wiring diagrams. The index will point you to the Blower motor so use a cheap digital multimeter to diagnose the problem. The Blower uses grounds G111 and G200....G200 is also used by the radio.
The index will tell you where to find the grounds.

Once you have fixed the blower check out the radio for good grounds and no blown fuses..some radios have their own fuse mounted on the rear of the radio or just inside.
Unfortunately the radio also uses the PCI bus so the fun begins here.

The cluster also uses the PCI bus. You may have to unplug the PCI bus from the radio to see if the cluster works and vice versa...the bus goes all over the place and one component holding it up can cause multiple problems.


I checked all fuses pulled the stereo and heater controls and did a hard reset by pulling the battery cables and clamping them together for a while. Now the gauges seem to work and no “no bus” light on. The heater control doesn’t work but I haven’t tried with the radio installed. Is there a specific spot I can look to check grounds? I found the wires but have no idea where those wires go to actually check a ground connection. The wires look ok. Battery cables are clean and tight. Any other ideas I can try? Would the heater fan switch cause this issue? I don’t want to just throw money at it.
 

jeepguy4276

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Also, where is the blower motor resistor? Can you get at the blower motor without pulling the dash? Can I leave the radio disconnected?
 

jeepguy4276

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I think you just need to pick music or airflow. :D

Ground issue possibly? I bet they're grounded to the same ground. Might just need to be cleaned up.

They use the same ground according to the manual. So how can I find where the ground attaches to the jeep? Everything else seems good.
 

jeepguy4276

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If I use the black ground wire from the radio and black ground wire from the blower switch and splice those together with a ground wire running to the dash or body, would that work to make a good solid ground for both?
 

kejobe

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If I use the black ground wire from the radio and black ground wire from the blower switch and splice those together with a ground wire running to the dash or body, would that work to make a good solid ground for both?

Don't see why not.
 

Runion

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Hello All
I hope resurrecting this string was not the wrong thing to do...
I read this through hoping to see how it was corrected.

I very recently bought a 2005 Jeep Liberty, pretty basic machine.
Had the factory stock radio, and it did'nt really work very well so
I replaced it with a Sony CDX GT930UI. All was well and I was
enjoying my new Jeep. Then 3 days ago, the RADIO and
Windshield WIPERS began to cut off intermittantly. Messing with
the Key switch in any way made no difference. If I drove it and the
RADIO/WIPER cut out, it may cut back in in 5 to 15 minutes later.

I got my mechanic to make a printout of the electrical system so I
could try to make sense of all this. Found the circuit where the
RADIO/WIPER both were connected to, which leads to a couple
of plug contacts and the ign switch.

Started testing voltage on fuses to try to get an idea where the
problem starts and the mechanic suggested pulling the WIPER
relay. So found the relays, and traded with the AC relay, which
was operating. The trouble, at least up to now, has gone away.

The AC is also working.
What makes this even more strange, this fix is not connected
with the radio circuits, and yet the radio is running fine again.

Just thought I'd mention this as at this time, the problem is gone
and I plan to replace the relay that was moved.

How this worked?? My best guess is the relay may have a contact
problem or the plug for the relay may have had some tarnish or
corrosion that made the contact intermittant. ?? Moving the
relay and plugging it in cleaned the surface of the plug to make
good contact. Maybe so... maybe not. we'll see.

This is what I did.....
 

Cardhu

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Hello All
I hope resurrecting this string was not the wrong thing to do...
I read this through hoping to see how it was corrected.

Threads only 3 months old, and not 8 years. Did much better than most post 2 members. You also suggested stuff that did work for you especially when thread open ended with no fix posted. Your fix was also inexpensive (bonus points)

Welcome to the forum.
 

jeepguy4276

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I’m sorry I didn’t post my fix that has so far worked. I did connect into the ground wires for the radio and the fan since the ground is ultimately shared. I then left the original ground wires all attached and just spliced a separate ground wire in. I took the separate “new” ground wire and attached it to a ground connection on the steering column. Worked like a charm and was an easy fix.
 
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