ZJ Four wheel drive switch

[rossman40]

1052541

I have a 94 Grand Cherokee Limited. The console keeps saying service four wheel switch. Where is this switch? I have one of the front axles without the disconnect so is this switch on the transfer case?? I have a sneaky hunch thats it is stuck in 4wd because my MPG went to crap.[addsig]

 

[dingus]

1052986

the switch is a vacuum mechanism. my first guess would be to climb under there and check that all the vacuum hoses are connected. if your MPG has gone south, my guess is that it is stuck ENGAGED in 4wd-high-full time. [addsig]