84 300 cdc new to the mb cannot figure out heat - Mercedes-Benz Forum

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post #1 of 2 (permalink) Old 03-23-2013, 02:20 PM Thread Starter
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84 300 cdc new to the mb cannot figure out heat

So a few weeks ago i purchased a 84 300cdc with around 350k on it. The price was right so i jumped. there are a few issuse to start all of the power windows were disconnected from the window frames along with the mounts. Once I completed all of the windows. I then changes most of the filters and fluids, except for the power steering filter. I have spent many nights on the web and days troubleshooting the car but i cannot figure out the acc. It has the unit with the wheel on the left, five buttons centered and the fan on the right. I am positive that the unit is being powered, using a multimeter, but i cannot get the blower motor to turn while it is conntected to the acc unit. The brushes are fine and will worok with aux power, though i cannot figure it out. All of the cold soldier joints are fine and the board in the unit is not burnt. I am afraid that i may be missing some of the original wires due to previous owner. if the monovalve is disconnected that would mean that it is locked in open position and heat should be my only option correct. If anybody could give me advise on how to trouble shoot the heating system in the car i would greatly appreciate it. I dont really care about the a/c the sunroof and all of the windows work fin and thats ok with me, unless the a/c needs to work correctly so the whole unit may.
Any help on this issue would be greatly appreciated. Is that a way to possibly hard wire the heat so i may just keep my windows defrosted. I have a long cruise back and fourth to work and that is the main reason i bought this car but if i cant find the heating issue i will only be a beach house crusier on a nice day. Thank you for reading sorry its so long, just have spent many sleepless nights because i cannt fgure this out and am normally very proficient in any issue with any car. Thanks
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post #2 of 2 (permalink) Old 03-24-2013, 12:59 AM
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