prezgully21

While driving home with the ac on The ambient temperature reading went from 75f to 185f on the dash and the check engine light came on when this happen the fans automatically came on and caused the climate control not able to turn back on I thought it would of been the sensor problem located in the front bumper but i changed it and it still reads 185f.. my ac allways worked fine before this happend any suggestions I need help!

greynlds

You'll probably get better responses if you ask in the GL Class (X164) forum rather than the G Class forum.

prezgully21

I did no answer in that thread thank tho

hookedon210s

Did you ever solve this problem? My 06 ML500 just did the same except no check engine light. I replaced the ambient air temp sensor and now when I first start the car the ambient temp gauge reads 50F briefly and then 185F. I wonder if any trouble codes need to be reset. Another problem I have had is a five minute delay in cooling when first operated for the day. I am convinced that points to a defective climate control unit. Mark

prezgully21

Still having the same problem I took it to a couple places and they said it mite be a wiring problem connected to the ambient sensor but it comes on and off when it feels like it still my check engine light comes on and off when it happens too

hookedon210s

After checking out the wiring harness to the ambient temp sensor and performing the resistance checks outlined in DAS/Xentry (the sensor feeds one of the CAN busses including the bus that the Climate Control Unit is on), I concluded that the CCU was defective. I obtained a used CCU from fleabay/LKQ (new is $1,200) which corrected the ambient temp sensor issue but has not corrected the 5 minute delay for max cool to engage. Further diagnosis points to replacing a shorted compressor to correct that malady. Mark

prezgully21

Hey bro I think I figured out what the problem was I was driving one day and the same thing happed 185 show on temp and ac console came off I got pissed and punched the console in the ac button and it came right back on and 185 went back to regular temperature 75f ice cold ac lol

hookedon210s

When all else fails get a bigger hammer. Sounds like your CCU has a cold solder joint. Replacement CCU solved my ambient temp. issue and the 5 min. delay on compressor full output was solved by replacing the compressor. Not a difficult job except replacing the receiver drier requires bumper removal and alterations to the radiator shroud to access. Stoooopid design IMO. Mark

prezgully21

I took out the center console and seen a a plug halfway out plugged it back in been working fine ever since all you neec is 2 flathead screw drivers to remove the clips are right over the slide out draw