I have a 2006 160LX that's developed some issues over the last little while. First back in Dec I was off loading it and it wouldn't shut off with the key so I brought it inside used the emergency shutdown and let it thaw for the night - this seemed to fix the problem until recently. As of last week it no longer shuts down with the key, the battery relay wont disconnect automatically and by the end of the week I noticed the A/C was running constantly and turning the evaporator into a block of ice. Today I went to work with it and the A/C cycled a few times and within 10min had failed completely. I checked the pressure - its good and jumped the compressor and it cools just fine. I cant seem to find any high or low pressure switches in the system unless its the one in the receiver/dryer. Also, when I press the A/C button in the cab I can hear a relay clicking behind the seat which I've looked for and cannot find even with the help of my parts manual so I'm assuming its likely part of a micro controller. I'm not sure if all these problems are related or just coincidence. I'm not getting any error codes on the display but I'm not ruling out a computer issue at this point. I'm hoping someone has experience with these machines on why it wont shut down and the a/c wont cycle. Hopefully someone has a wiring diagram with more detail then the parts manual or maybe knows how to access the on-board diagnostics - there might be something useful in there.
I solved the issue, I finally remembered to bring a meter out with me. When I checked the voltage on the a/c circuit it was fluctuating between 9-28v and had a short from the compressor to ground and a open (sometimes) from the pressure sensor side. I found part of the harness rubbed though just above the starter and shorting out. Everything works as it should now and even shuts off with the key, I never would of guessed the engine shut down ran through the alternator. If anyone else gets a/c problems, failure to shut down with the key and sometimes random alternator warnings the harness beside the starter that runs with the a/c lines may be a good place to start.
Always good to hear a success story.