ok so my dad came home and i went outside with him and did what you told me i counted three from the left and i landed on the button labeled EC and when i pushed that the ac compressor didnt spin howeever if i pushed the other buttons, the compressor was spinning. so what should i do next??

EC is four from the left.

The middle button is the third from the left.

My previous post asked you to make note of how long the compressor is engaged with the middle button depressed.

You failed to provide this info.

ok i will retest. sorry i didnt follow directions. =[ and mr.carlton i wanted to say thanks soo much for all your help i really appreciate it!

Your previous statements were that the compressor engaged for a short period of time and then it disengaged.

I'm looking to see how long this period of time is.

I'm also looking to see if the system resets and provides another cycle of engagement if you shut the engine down and start it up again.

ok so i just went back outside for a time of 5 minutes i ran the third button and the clutch didnt stop turning it was turning and turning never stopped.

ok so i just went back outside for a time of 5 minutes i ran the third button and the clutch didnt stop turning it was turning and turning never stopped. oh and inside justtttttttttttttttttt a little bit of air was comming just a little bit

Go outside and do the exact same thing.......press the third button.......and then press the button for the high blower speed. It's the top button of the three buttons on the right side of the panel.

Report back as to whether you get maximum blower speed and the temperature of the air.

it was on high when i tested it first. and it was just comming out a little almost nothing.

OK, so, it appears that you have a problem with the blower........not with the a/c system........correct?

i guesss so =] thank you sooooooooooooooooooo much for your help thank you thank you thank you!!!!=] do you think i should take it to themechanic or should i fix it with my dad?

Depends what's wrong.

First step is to find the blower and apply 12V directly to the blower itself and see if it's working. If it is working, then you have a control problem..........it gets more complicated from there and you might need to bring it to a mechanic at that point.

If the blower has completely failed, you can remove it and replace it with our assistance.........if you have some decent hand tools.

this morning when i turned my car on i put pressed the third button from the left and the ac worked. however when i turned the ac off and then back on for the 2nd time it took some time but blew at full speed again. The third time that i turned it on it didnt work at all. Do you still think its a blower motor issue?

Nope......not the blower motor.

Either the problem is the CCU itself (likely) or the blower motor controller (less likely).

Brian

I am following this thread to see if the tests you are providing will lead me to my problem.

Let me know if I should start a new thread, but here is how far I got. Its an 86 300 SDL with 134a, good cooling for over two years until this month. I followed the tests in supplement A of the 126 ACC FSM. The clutch will engage for about five seconds, (about two minutes when cold) and repeat each time I reboot the engine.

It passed the low pressure switch (S31) test. Next was pull the KLIMA (N6) and check voltage between socket 5 and 1 and it had battery voltage. It passed the voltage test between sockets 5 and 10 for compressor voltage from S31 to N6. Bridging sockets 5 and 7 engaged the clutch and it stayed engaged until I shut down (5 minutes) for the next test. It failed the next test, checking RPM sensor for AC compressor between 9 and 11, with 5 and 7 still bridged, it called for 0.3 Volts~ and I got zero. The speed sensor resistance between 9 and 11 passed as well as the RPM signal from EDS > 2.8 volts~.

At this point the manual says replace N6 which I did and nothing changed.

My cheap set of gauges played out and I have a decent set coming from ackit.com, shipped yesterday.

Thanks.

Harry

I had the same thing.

You need to do the same test. Pull the Klima and check for continuity to ground on socket #10 with the ignition on and the middle button depressed.

It should show continuity for about 5 seconds and then go open. I don't think the results will change, but, if this does not happen, please start the engine and perform the test again.

That's a CCU problem if you confirm this.