98 S70 GLT No Air Conditioning/Heat/Fan

[Alecw81]

I snagged a "new" climate control unit from a 2000 C70 today, and of course now I'm not seeing any flashing lights at startup with the old one still installed.

[scot850]

Typical! Maybe the system just needed time to re-set itself. Can you return it?

Neil.

[mta58]

I have 97 850 GLT & the AC works intermitantly (whenever it feels like it). I don't believe that it's the fan itself but possibly a switch or a control device of some kind. Does anyone have any ideas where to start my quest ?? Any pics re the fix would help - I'm a novice.

Thanks
Mikey

[abscate]

These cars are known for intermittent AC due to the clutch gap wear problem

Search for 'bread clip fix' or 'zip tie fix' or ziptie fix to read about how to fix this cheaply.

[scot850]

Do you have ECC or regular A/C unit in dash? ECC has 2 small temp sensors, one hidden behind each grab handle above each front door. Regular A/C does not have this.

There are a few issues, and I think abscate has hit the regular first issue at this age. The other issue that can be there are:

1) Fuses - typically nothing will work
2) Fan motor bearings fail (doesn't work at all) or becomes intermittent. This can be affected by accelerating and stopping causing the bearings to lock up and free off which will make the fan intermittent.
3) This is less likely as you have a system the works some times, but the power stage or resistor pack. Not sure regular A/C has this.
4) If you have ECC the cabin sensor clog up over time preventing the little sensor fans running. Remove them and clean the crap out and clean with IPA carefully, then give the bearings a little silicon oil or light oil.
5) Low pressure in the system, needing re-charged. Have a vacuum pulled to check system integrity, and then have the system re-filled with a dye and the freon/oil mix and check the system maintains pressure. If you get a rapid or steady reduction in performance then it is likely the evaporator has failed. This is a big job requiring a dash removal. There is a good how to on MVS as I recall, I used it and it was great.

Neil.