My sister's landi (that I work on). Does not have working AC. The clutch is not engaging. I hooked up gauges and it's got 90lbs of R134a. I jumped the the clutch and it engaged just fine. I put a jumper in place of the low pressure switch (I dont know how I could get leads on it accurately to ohm the switch out. I'm wondering if anyone has some tips on what to check next. The AC switch lights up in the HVAC panel when you turn on the AC. It does not have rear ac if that makes a difference. When I looked at the fsm it said to check the AC relay but I couldn't figure out where that is (built into the relay bock under the hood??). Thanks for your help, I've been a reader of i8mud for a while, 1st post.