Has anyone ever had any luck with taking apart the hvac controller (84 to 96 type) to clean the contacts to restore power to the blower switch?

 

Blower switch as in the 4 position rotary **** that controls the flow of air into the cabin? Low, med-lo, med-hi, and Hi?

Have you taken the panel out to look at the back of the switch? They are notorious for melting and leaving you with only 1 or 2 blower control settings. Also the resistor under the passenger dash near the blower box will keep your blower from working correctly.

The switch is $15 from what I saw. Sounds worth it to me to buy a new one.

 

Do you have no power to the blower or does it only work on high?

If only on High, it's most likely the blower resistor like RockyMtn96XJ says.

You can remove the panel (be careful with the vacuum lines) and spray some contact cleaner in it, or replace it. Check the connector for any scorch marks'

https://www.quadratec.com/p/crown-au...nd-sj-j-series

 

I also had a problem with the switch. Seems that the housing for the wires that plug into the switch had failed by melting. I replaced the switch with a new one, put thermal ends on the wires and attached them directly to the switch, and replaced the resistor by the blower. That was about 10 years ago and haven't had a problem since....hope this helps

 

I went the whole hog and bypassed the entire system, by placing 3 relays in the kick panel for the 3 lower speeds, on my '96

Otherwise the full current must run thru miles of wire and switches, including the ignition switch

Eventually your fan may want more startup current, or hot joints develop, I think the fuse is 25A but thats a lot running all that distance

The plastic insulator material on these age XJs is not the best either

now only milliamps flow in the factory harness, not Amps

I avoid setting 4 (max), as I did not relay it out

 

I overdid it a bit and installed one of these instead of individual relays

https://www.holley.com/products/elec...parts/75643-HC

 

Any solutions to the hvac selector killing power to the blower when you switch from say floor to vent or defrost? This whole system is a mess on both my 95 xjs. Would love to hear of any alternative fixes. I replaced controls only to have it fail again within a couple of years.

 

Any updates?

Edit: Still waiting.

 

relays are the only truly adequate solution