I Have a 1988 Buick Century 3.8L. The Air clutch copressor activates
only when the radiator fan turns on. When the fan turns off the clutch
de-activates.

Any ideas

Gaetan

---

Request for Question Clarification by wengland-ga on 14 Jun 2002 11:19 PDT

Are you referring to the air conditioner compressor only coming on
when the engine fan is running?

If so, many cars ( I don't have specific information on the 1988
Century), have a lockout that requires the radiator fan to be on for
the A/C compressor to run.  Most of the time, when the switch is set
to run the A/C, the radiator fan will also be turned on.

It may be that your problem is the switch or relay that is supposed to
turn on the radiator fan when the AC is turned on is malfunctioning.

If this is what you are talking about, let us know, and I (or someone)
will dig up the schematics for your car and part numbers and test
procedure.

Thanks!

---

Clarification of Question by canuck2-ga on 15 Jun 2002 08:11 PDT

The air conditioning compressor clutch ONLY activates when the
electric fan to the Radiator activates.  When the radiator fan shuts
down the Air conditioner clutch de-activates and warm air is pumped
through the vents.

When the clutch is activated cold air is pumped through the vents

Hello Canuck2,

This certainly sounds like an electronic or sensor fault.  Due to the
extra heat generated by the condenser, most automobiles will either
have a bit of electronics to activate an electric radiator fan or will
have an extra fan mounted that is solely connected to the AC.  From
the description of the problem it appears as if the Buick Century has
a sensor to indicate that the AC is on and that the radiator fan
should be run.  This is what appears to have failed.  There also seems
to be another, completely separate, sensor that will not allow the
clutch on the AC compressor to activate if the fan is not operating, a
wise move since the AC consignor is located in front of the radiator
and heats the air before it reaches the radiator.  This could cause
overheating and the resulting engine damage.

If you do not have a Hayne's or Chilton's repair manual you might
think about picking one up.  They may also be available from your
local library.  Amazon shows a Hayne's manual that covers your car but
does not show a Chilton's manual that covers your model year.  You can
pick up these manuals from most any auto parts store and many discount
retailers such as Wal-Mart or Target.  The manual should have a
troubleshooting guide as well as instructions on how to replace the
faulty component.

Link to the Amazon listing for the Hayne's manual:
http://www.amazon.com/exec/obidos/ASIN/1563922096/ref=pd_sxp_f/002-2294376-0804822

There are used copies available on Amazon as well as new copies.

Link to Chilton's Online:
http://www.chiltonsonline.com/

You can purchase the book that covers your model year Century.

Link to ChiltonDIY.com
http://chiltondiy.com

All Chilton's manuals online for a yearly subscription fee.

Search terms used:

"haynes manual"
://www.google.com/search?q=haynes+manual&sourceid=mozilla-search&start=0&start=0

"chiltons repair"
://www.google.com/search?q=chiltons+repair&sourceid=mozilla-search&start=0&start=0

"haynes buick century"
://www.google.com/search?q=haynes+buick+century&sourceid=mozilla-search&start=0

markoft

In my personal car, I know that both the Fan, and the A/C are on the
same Fusable Link. If the link goes, they both die. (I have a 1989
Ford Tempo) As it just so happens, this is what has just happened to
me. :)

googlebrain-ga

After reviewing the wiring diagram the only common link between the
cooling fan and the compressor is the ECM (engine control module). You
can usually purchase a used ECM for 40 dollars at any auto dismantler.
This silver box is located under the dash on the passenger side. The
only other likely possiblity is someone has tampered with the wiring
and created a jumper wire in an attempt to fix a faulty A/C circut. A
thorough diagnosis of this electrical system will not take more than
one hour by a qualified mechanic (approx $65.00) this might be the
best thing to do. View the wiring diagram here:
http://noes.net/88century.pdf