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'85 300D Climate Control and Hazard Flashers failed

Around the same time, both the climate control and hazard flashers in this car have failed.

The climate control has a horizontal row of buttons for "function" I guess, a dial for temperature, and a set of fan buttons that sets the fan to high, low, or "auto".

Opening up the CD-based 123 manual, the pictures are all of the ACC system like in my '79 TD, but is the troubleshooting otherwise useful?

The actual, complete symptoms are that the fan never turns on. The A/C compressor is frozen and there's no belt on it, but it's been that way for some time.

Noticed at the same time is that flicking the hazard signal switch yields nothing at all. The light goes out on the switch, but it doesn't flash. The turn signals, however, operate properly.

Any tips on either of these?

thx,

-tom!

Reply to
Tom Plunket
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I'd check the fuse... remove and replace with new one.

Reply to
Tiger

Yeah ok so the blower was the fuse, and the hazard flashers mysteriously started working again, even though I'm pretty sure the documentation puts them on a different fuse.

However, we've since noticed that the turn signals frequently stop working. Flicking the hazards a few times will bring them back to working, but this happens at least once a day. Any thoughts on what we can try disassembling and cleaning to make this no longer necessary?

thanks for the guidance,

-tom!

Reply to
Tom Plunket

I would change out all the fuses you got... those aluminum one are really junks... they will oxidize without looking bad until you take them out... then they fall apart because of no electrical contact.

Reply to
Tiger

Keep digging in the CD manual. You have auto climate III, I think it is called, and it's in there, but you do get to the system you have found first.

Paul

Tom Plunket wrote:

Reply to
heav

This sounds like you have several different problems. Your blower motor may have failed if you get zero fan operation. It's in the black box under the glove box and can be removed easily. It's held in place by 3 8mm head screws. Take it out and use a 12 volt power source to see if it will run. If it won't go you have discovered what is wrong. If it does run, then you should check the switch on the control unit. Be careful with the control unit. It will cost you $500 to replace it if you mess it up.

Be sure you have replaced any fuses first, of course. Do you live in a place with a humid environment? You may have corroded contacts in various places which could cause the symptoms you describe. You have to remove the ash tray holder bracket and then you can slide the faux wood cover over the window switches and hazard flasher switch back and it will come up and you will be able to get to the switches and the flasher unit. Just disconnect and reconnect all the harnesses. Squirting contact cleaner (don't buy the kind that contains lubricant, use the kind that says "leaves no residue" Radio Shack sells it) will make this work better. You can also try a squirt or two of this in the switches.

Obviously you need to rebuild your AC system. D> Around the same time, both the climate control and hazard flashers in

Reply to
heav

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