1996 XJ 242 cui, 354,000 mi.

Blower switch was not turning on blower after work yesterday. I usually just leave it on high and select vent or defrost, whatever.

Back in the early 2000s the connector behind the switch was diagnosed as burned out and the shop re-pinned it with individual connectors, then to the switch connectors (as described to me). They missed the light connection somehow.

Big question, anybody seen a replacement/mod to this switch, like a heavier duty rheostat or heavier duty switch? Am I stuck either checking and cleaning this one, or finding one in a junk yard?

 

after studying the circuit diagram for '96 and earlier, imo, there is no other option but to relay out each wire at the resistor pack inside the vehicle..so 4 relays.

I have them here waiting to do $15

Some may consider this overkill, but otherwise every electron flows thru a stack of wiring harness, all switches and the ignition switch!

Chrysler engineers rectified this issue in 1997

 

BTW, the blower started up after I turned everything off and on, cycled through, etc. a few times.

Is replacing my 1996 stuff with 1997 stuff an easy enough option, or are we talking a big mess? Also, when I replaced the ignition switch this summer it had some melted insulation and signs where the smoke came out a little. Was probably a premature replacement, starter was the problem.

 

If you want your fan activation system to live..follow me..or it will die

only milliamps will flow thru all the wiring harness, ignition switch, heater switch etc

You cannot reverse engineer to the later post 97 system, as it is based on earthing the system (how it should be done in the first place)

the fan kicking off can probably pull 20 amps..more if near stalling due to some issue..imagine that going thru the ignition switch, no wonder they melt on pre-97

 

Any tutorials on this mod? And, most importantly, does it disqualify an XJ from inclusion in the survivor thread?

 

I've been told by several Mopar techs that you should set the blower speed at 2 or 3 before you turn off the engine because it pulls less amps on startup when it's restarted. Set on low, all the power goes thru the largest tap on the resistor and can burn that out, or set on high, can burn up the switch. It all comes down to amps the blower motor draws as it ages and the condition of the motor bearings. Dry bearings in the cold put way too much load on the wiring.

97 and later circuits supply power directly to the blower motor and the 3 resistor taps and direct high speed wire form the ground paths. On the early models, simply move the supply wire to the motor and ground the switch supply wire. No relays needed. This will effect polarity of the motor and require switching the 2 motor wires for rotational direction.

 

I think I would get the switch if you can find it and about 12 inches of the wires from a donor Jeep from the junk yard (or deadjeeps, etc eBay) and splice them in. Replace the resistor if needed then check visually to ensure nothing is binding your blower fan or otherwise causing it to pull too many amps that burns up your switch/wiring.

Quoting CCKen from another thread:

Some folks have deleted the plastic connector altogether and went with new wire terminals only. See pic.


The terminals are Delphi/Packard Type 56, female, open barrel, .250" blade, 12 gauge wire, terminals. To properly install them you will need a special crimper, but you can be a little creative crimping the open barrel.


There are plenty vendors selling these terminals, including Evilbay.

 

I will do a write up when I do the install.

basics are;

* fit 4 x relays with holders to small strip of wood or plastic, adjacent to resistor pack... (so you wont be able to see it..so Yes..Survivor thread imo)
* wire up the 4 resistor pack input wires, one to trigger each relay, relay output to each male pin on resistor pack
* run fused 12V wire from battery thru firewall to power relays

high current only flows thru the relays..any other configuration (such as just one relay), means something has to take the full current (such as your failed switch)..probably get one from wreckers

The ignition switch is the big deal though, I better hurry up & do it !

 

Thank you.

And switch isn't quite failed yet. Acts like it is just worn bad or something.