1987 300E aux fan switch? Also temp gauge ?

#11

On May 12, 9:59 am, "Tiger" <tiger0... (AT) hotmail (DOT) com> wrote:

Quote:

Your car might be slightly different but not much different. Your car is
similar to my previous 190E setup. I believe you got only one speed fan.

I would first jumper the temp sensor by your AC accumulator/drier... not the
black one on the top... but the one on the side... probably green or red.
Touch the two bare terminals together to see if your fan comes on... If no,
then you need to check elsewhere.

As for the sensors you have on the top of the engine... the two prong is for
AC and the three is for engine to trigger your Aux... My suggestion is
change those out due to age unless you changed them before. To change these,
engine must be cold.

The relays are in your fusebox... you need to loosen 6 screws and remove the
cover of the fusebox... There will be colored relay with a fuse on it... if
you have two of them... blue and green, then you actually have two speed
aux.

Another tip. Get a test light and see if you have 12V making it to
the wire end at the fan. Often inline connectors get corroded. So,
while the fan could run if you hook a wire from the battery with 12V
to it, the connector to the fan could be bad on one end and the normal
12V is not getting there.

#12

Thanks for the info. I was able to jump the ac switch as you described
and the fan did come on. I also jumped the 105/115 switch on the head
and it came on high speed. I'm not certain that the car has gotten hot
enough to activate the 105 switch, so I'm not sure if that is bad or
not. As for the AC switch, the 134A was low, and I've just charged it,
so with out proper coolant levels, I'm not sure the switch would have
activated either. At least I know the circuits are intact and the fan
does work with activated (no relay or fuse problem...) I'll have to do
some add'l work to make sure the two switches are functional though...

thanks again for the info. the labeled photos, schematics, and
comments here are really helpful.

--
tsh24

#13

What color is that temperature switch? Is it green or red? You converted to
R134a... so you need a lower temp switch to activate the aux fan. The red
one is used for R134a System... if you have a green one, it would never come
on... just like mine.

I installed the green one when I fixed the system and realized that the
factory installed the red one... I thought it doesn't make any difference
but ha! aux fan never come on.

I am still waiting for the red one to come.

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1987 300E aux fan switch? Also temp gauge ?

Mercedes-Benz Mercedes-Benz Cars Discussions (alt.auto.mercedes)

Re: 1987 300E aux fan switch? Also temp gauge ? - 05-12-2007 , 04:14 PM

Re: 1987 300E aux fan switch? Also temp gauge ? - 05-13-2007 , 07:06 AM

Re: 1987 300E aux fan switch? Also temp gauge ? - 05-13-2007 , 02:31 PM