HEADACHE WITH AC/blower etc! w126 - PeachParts Mercedes-Benz Forum

egutie6970 · #1 06-10-2006, 12:30 AM

Well, about 2 months ago, i was driving i had my heater/blower on since it was cold ( it was on economy at full blast). My ac was not working because it did not have freon. All of a suddent as i was driving, the thing that blows air into the vents stopped. I was almost home so i figured ill check it out tomorrow.

Well fast forward, it has never been working again. No more air from the vents.

Now i want to fix my AC, my compressor does not engage, my blower does not blow, i took off the blower ( the thing that spins on the passanger side) and i took off the wires, and put it on my electric read out ( a light bulp) it did not light up. I went to the front of the compressor, did the same, nothing, i checked rellays, nothing.

Where else should i check ? this thing is driving me crazy! I would like to get this fixed before summer school starts. I would appriciate any advice/tips on how to check whats working and wahts not.

So far it seems like my :
Blower does not work
AC compressor does not engage
Fan infront of the condensor does not engage

So im guessing something is mest up with the cooling/heating system--but i have no idea what! Thanks guys before i g o

GVB · #2 06-10-2006, 01:56 AM

Replace the bad fuse.

egutie6970 · #3 06-10-2006, 02:17 AM

the fuse looks good....i switched the relays and same problem..

Which fuse/relay do you think it is ?

rchase · #4 06-10-2006, 02:32 AM

Quote:

Originally Posted by egutie6970

the fuse looks good....i switched the relays and same problem..

Which fuse/relay do you think it is ?

Do yourself a big favor. Before you do ANY more diagnostic work go down to your local parts vendor and get a full set of fuses for your car. Mercedes Fuses are known for corrosion issues and while they might "look" good they might not be providing a good connection. Also don't do the glass fuses. They never work quite right and have a tendancy to blow frequently.

I had a number of electrical issues in my 300SD that completely went away with new fuses. They are cheap and will save you a ton of headaches.

egutie6970 · #5 06-10-2006, 03:16 AM

i just went out to do as you said

I replaced all the blue ones
Red ones
and about 75% of the white ones

I ran that light bulp thing to see if it was getting current... its weird If i have the positive thing touching one fuse and touch the same fuse- it dosent light up, if lights up with only some of them that i touch ( other then the one im touching with the positive side)

is that the way it should work?

sixto · #6 06-10-2006, 03:22 AM

Is the key in RUN? Some circuits aren't live when the key's out.

Sixto

egutie6970 · #7 06-10-2006, 03:26 AM

the key was turned to the 2nd tick- baiscly all the way but i didnt start it .

egutie6970 · #8 06-10-2006, 03:27 AM

wow sixto your located in teh bay area ?! so em i !

Maybe i should take the car to you so you can fix it for me ! :y !

rchase · #9 06-10-2006, 03:57 AM

Quote:

Originally Posted by egutie6970

i just went out to do as you said

I replaced all the blue ones
Red ones
and about 75% of the white ones

I ran that light bulp thing to see if it was getting current... its weird If i have the positive thing touching one fuse and touch the same fuse- it dosent light up, if lights up with only some of them that i touch ( other then the one im touching with the positive side)

is that the way it should work?

The fuses are usually run on the positive side of a circuit so touching your light to both ends of the fuse does nothing. Vehicle electrical systems (in most cases) are 12 volt negative ground meaning that you can get the negative side of the battery by touching any part of the metal frame. If you put one side of your lightbulb on a metal object thats grounded and then touch it in the fuse box you will be able to do your testing.

Better than a light bulb would be an VOM to measure the conductivity/resistance of the fuse. Additionally if your only getting 2v at the end of your circuit it might be enough to light your bulb yet not tell you your missing 10v of power. You can get a cheapie at radio shack for $10.

Just for future reliability I would finish the rest of the fuse box as it will save a lot of future headaches.

egutie6970 · #10 06-10-2006, 04:03 AM

thank you ! i will do just that tomorrow!

Jim B. · #11 06-10-2006, 05:36 AM

Quote:

Originally Posted by egutie6970

wow sixto your located in teh bay area ?! so em i !

Maybe i should take the car to you so you can fix it for me ! :y !

Be careful, those Bay Area Mercedes mechanics charge *high* I was there to end of 2004 and boy do I know about that!!!

egutie6970 · #12 06-10-2006, 04:13 PM

alrite i just checked and nothing.... whats next guys ? before i start pulling out my hair !

All thje problems-related to:

Compressor
Fan infront of condenser
Blower/no air from vents

Is there like a computer thing that tells al lthis how to work ? because relays are okay/fuses okay...just no power to these devices...everything else is fine....

RAYMOND485 · #13 06-11-2006, 10:48 AM

1984 300d Turbo
Go To **************.com For Fuse Kit And Other Kits, Remove Plug From Blower Motor Check For 12 Volts Remove Blower And Have It Check By A Auto Electric Shop It They May Repair, **************.com Have The Repair Kit $28.00 And Guide Book

rchase · #14 06-11-2006, 12:19 PM

Quote:

Originally Posted by egutie6970

alrite i just checked and nothing.... whats next guys ? before i start pulling out my hair !

All thje problems-related to:

Compressor
Fan infront of condenser
Blower/no air from vents

Is there like a computer thing that tells al lthis how to work ? because relays are okay/fuses okay...just no power to these devices...everything else is fine....

I did not want to mention this BUT the Klima module is located behind the center wooden panel in your 126. Its expensive and should be a last resort for replacement but may be the part that's failed. I would suggest taking the car to an indepndant mechanic at the point where you have done everything you can. My mechanic charges a standard diagnostic fee that he applies to the repair if you have the repairs done by him.

I do a lot of DIY work but recognize there is distinct line that I don't cross when it comes to projects I don't understand fully. There are a lot of backyard mechanics that jump right into jobs that are too complicated for them without doing the research and end up damaging their cars in the long run.

I wish you the best of luck and hopefully its a cheap repair.

egutie6970 · #15 06-13-2006, 01:17 AM

Quote:

Originally Posted by rchase

I did not want to mention this BUT the Klima module is located behind the center wooden panel in your 126. Its expensive and should be a last resort for replacement but may be the part that's failed. I would suggest taking the car to an indepndant mechanic at the point where you have done everything you can. My mechanic charges a standard diagnostic fee that he applies to the repair if you have the repairs done by him.

I do a lot of DIY work but recognize there is distinct line that I don't cross when it comes to projects I don't understand fully. There are a lot of backyard mechanics that jump right into jobs that are too complicated for them without doing the research and end up damaging their cars in the long run.

I wish you the best of luck and hopefully its a cheap repair.

Is there anyway i can check the Kilma Module before i decide to go for it ? You dont htink its my thing - were i click what i want on the center console ? climate control ? i think thats what its called haha..