If you've properly done the test, you've confirmed that the problem is the CCU and not the Klima. Get another CCU and the problem should be eliminated.

Found a CCU on ebay:
W126 1986-1991
300SE / SEL
420SEL
560SEL / SEC

Note: This may fit more models than indicated above. Buyer is responsible to verify compatibility with their own car and unit.

Part number: 126-830-08-85

I have a W126 300SDL
part number 126-830-05-85. Des anyone know if the
above model will work?

That one should have the horizontal plugs on the side. 81-85 are vertical. It should work on your 86 or 87.

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

Probably just an updated unit, all '86+ ones interchange.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

That is what I wanted to hear.
Thanks guys
A

Fighting the A/C woes also?

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

How high on the model can I go?
I see some with Part numbers all the
way up to: 126-830-11-85
Still looks like the one I need,
Part number: 126-830-05-85
As long as the pins line up,
is it good?
A

Not the CCU.
Mechanic took the Klima out and wired straight from
CCU to condensor with a fuse in between(slick). AC is on all the time but it feel
SOOOO good. So I will replace the Klima and go from there.
And the air is cold. Not as cold as my VW but cold
enough to keep everyone comfortable.(and that is what it's about,comfort)
I am not trying to freeze myself A** out of the car. I do believe that the
converting was the right move. Conversion(dryer,switches, labor) and troubleshooting came in just under $225.
Good luck to the everyone battling this same ordeal.
A

Based upon your previous tests, and provided you did them correctly, the problem is the CCU. It's not providing a ground signal to the Klima.

So, if the mechanic wired the compressor to run all the time.......as you stated........he has bypassed both the CCU and the Klima.

In such a case, you have no control over the evaporator temperature and will likely freeze it in conditions that don't demand the compressor to be engaged at all times.

A replacement CCU would have probably cured your issues.

Brian,
The CCU is responding thought.
Temp dial works, push buttons work
fine. Is there any way just to test the
CCU?
Thanks
A

Does the economy pushbutton function as designed? Meaning.........if you press that button.........will the compressor shut down?

I will give it a try.
A

Put in new Klima and it worked great........
But then.....
Boom, the compressor poops out.
Searching for a rebuilt.
Summer is almost over so will not wory till
next summer. Hope to have compressor
installed before next summer.
A

Early 300E comps work in these vehicles, should help the search.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

Order a new dryer and expansion valve, if there is one, with that compressor, and have the system completely flushed to get rid of the possible metal shavings spewed out of the compressor just before it failed.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D