The ac and heater in my 1999 cadillac deville won't work what could we do to make it work

Visit the on-line store, know as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem. Deville 1996 1999 Factory Service Workshop repair manual

Is your floor wet on the passenger side up front and smell like antifreeze? If so, the heater core blew, but it's not hard to replace.

Lifted from another FixYa page...............

Follow this step for clear the a/c codes on your cadillac el dorado 1999.

The fan assembly is under the glove compartment. Remove cover[3 scews] unplug electrical connector. then remove the 3 bolts that hold the fan assembly in the housing. take motor apart and clean check brushes in brush holder, then sand the armature where the brushes ride. Stretch spring on brushes , the put the motor back together. works 95% of the time.

Hello,

Here is detailed solution on how to replace the heater core in the 1999 cadillac deville;



STEP 1 Disconnect the negative battery cable.


STEP 2. Drain and recycle the engine coolant.

STEP 3. Disconnect the heater core hoses using tool J-37097 or an equivalent.

STEP 4. Remove the right side sound insulator and the glove box module.


STEP 5 Remove the programmer shield, if equipped, and disconnect the air mix valve link.

STEP 6 Disconnect the programmer vacuum and electrical connectors.

STEP 7 Remove the heater core cover, leaving the programmer attached.


STEP 8 Remove the heater core retaining screws and the heater core.



have a nice day..

make a jumper cable up from lamp cord (from any Hardware store) and power up the blower motor from the battery

loose spark plugs can cause this to happen

I HAVE A 1998 CADILLAC DEVILLE,THE AC BLOWER MOTOR GETS HOT AND TURN OFF AND WONT TURN BACK ON UNTIL IT COOL OFF, WHAT IS THIS PROBLEM?

Have your a/c system charged and tested for leaks.