For 4.5 years of 5 owning my 200 the AC stayed set at 74 degrees, faithfully keeping me comfortable. The only time I remember messing with it was for certain summer stretches of north texas on my way to colorado where I had been in the car for hours.. needing to bump it up to 75.
Then, a few months ago, seemingly out of nowhere, ice cubes in my face. But only when sun was directly hitting the solar sensor in the center of the dashboard. 78, even 82 was needed. I once had to go as high as 84. But if a cloud comes along.. within seconds, warm air flowing out of the vents.
Needless to say, my mind started trying to figure out what's going on.
I did the AC servo initialization.
I verified the cabin temp sensor in the dash was free of dust, even pulling the panel and blowing out the rest of the corrugated hose behind the sensor.
I verified recirc flap is working as intended.
None of these things helped.
For the record when this happens it is out of both right and left vents. AC on auto, rear AC off, 4-zone disabled.
Using techstream I verified cabin temp sensor accuracy, it is perfect. I checked operation of the solar sensor.. while I have no frame of reference to say full sunlight should show X number in live data, it did drop to nearly zero when blacked out, and the numbers seemed to rise in proportion to the amount of light. Plus, the sensor apparently has two sides, and both seemed to operate appropriately. I figure if it was a sensor failure with two independent sides, both wouldn't fail the same way at the same time.
So.. thoughts? It's almost like the control strategy for sunlight sensing suddenly shifted to be much more aggressive. One thing rolling around in my head is possibly low refrigerant.. I've read about a few people addressing odd issues with an evac and recharge. Maybe in my case it is overcompensating.
Also, if someone has time, can you boot up techstream and get a solar sensor reading? Mine went as high as 138 in direct sunlight.
I'm attaching what the FSM has to say about testing the solar sensor, but haven't gotten around to pulling it and checking. Plus like I said both sides failing at the same rate seems implausible. I'd just toss a new sensor in there but it's a fair amount of money for something that seems to be working correctly in techstream.
Thanks for any help
Then, a few months ago, seemingly out of nowhere, ice cubes in my face. But only when sun was directly hitting the solar sensor in the center of the dashboard. 78, even 82 was needed. I once had to go as high as 84. But if a cloud comes along.. within seconds, warm air flowing out of the vents.
Needless to say, my mind started trying to figure out what's going on.
I did the AC servo initialization.
I verified the cabin temp sensor in the dash was free of dust, even pulling the panel and blowing out the rest of the corrugated hose behind the sensor.
I verified recirc flap is working as intended.
None of these things helped.
For the record when this happens it is out of both right and left vents. AC on auto, rear AC off, 4-zone disabled.
Using techstream I verified cabin temp sensor accuracy, it is perfect. I checked operation of the solar sensor.. while I have no frame of reference to say full sunlight should show X number in live data, it did drop to nearly zero when blacked out, and the numbers seemed to rise in proportion to the amount of light. Plus, the sensor apparently has two sides, and both seemed to operate appropriately. I figure if it was a sensor failure with two independent sides, both wouldn't fail the same way at the same time.
So.. thoughts? It's almost like the control strategy for sunlight sensing suddenly shifted to be much more aggressive. One thing rolling around in my head is possibly low refrigerant.. I've read about a few people addressing odd issues with an evac and recharge. Maybe in my case it is overcompensating.
Also, if someone has time, can you boot up techstream and get a solar sensor reading? Mine went as high as 138 in direct sunlight.
I'm attaching what the FSM has to say about testing the solar sensor, but haven't gotten around to pulling it and checking. Plus like I said both sides failing at the same rate seems implausible. I'd just toss a new sensor in there but it's a fair amount of money for something that seems to be working correctly in techstream.
Thanks for any help
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