1994 Lincoln Town Car AC not working- tested Eatc cant find

Tiny
TRACY747
  • MEMBER
  • 1994 LINCOLN TOWN CAR
  • V8
  • 2WD
  • AUTOMATIC
  • 98,000 MILES
Ac not working just blows heat, at temp set to hot or cold. Vents blow hot air.

I can hear the compressor cycling, it cycles to much every minute or so it clicks. It was replaced by the dealer.

I tested Eatc through temp display, cant find code definition for 02.

How do I check for a vacuum leak to make sure this is not the trouble?


i have a new eatc module, I am afraid of the work invovled replacing unit. Removing dash bolts dropping down steering wheel, Lifting back dash to snap in new module. Sounds easy

I just want to make sure that the Eatc is the problem before tearing apart the dashboard.

TRacy
Do you
have the same problem?
Yes
No
Thursday, December 4th, 2008 AT 5:58 PM

5 Replies

Tiny
JASONRAY
  • MEMBER
To check for a vacuum leak, it's usually easier to start at the actuator itself if you can get to it. If you can, unplug the vac. Line from it. With the vehicle running, move the switch back and forth from hot to cold and see if there's any vacuum at the line you just unplugged. Keep in mind that it will be a very small amount of vacuum so it's not going to suck your finger to it real hard like a brake booster line. If there is vacuum there, then the actuator is most likely bad. The diaphram inside them can go bad and not move the arm when vac. Is applied. If there's NOT any vac. Move to the control head in the dash. You can remove it without tearing a lot of the dash apart. Unplug the vacuum connector at the back of it. Again, with the engine running, see if there is ANY vacuum on one of the lines. If not, go under the hood. Look for a black vacuum line going through the firewall into the passenger compartment. It will come from the engine or maybe even the line going to the brake booster. There will be a small black "check valve" inline. Check that line where it originates and see if there's vacuum there.
Was this
answer
helpful?
Yes
No
Thursday, December 4th, 2008 AT 6:22 PM
Tiny
TRACY747
  • MEMBER
Will the vac or Eatc repair - fix the AC so it will work?
Properly, the heat rolls out of those vents with no sign of AC output.

With a broken EATC: Can you have the AC and Heat on at the same time in the car, in a 94 lincoln, so if Vac or EATC is replaced/repaired. The AC should work.

The ac was repaired at the dealer one year ago, they did it twice for me. A Leak pressure test, new ac unit etc. And it was very cold when they got done with it. Now it is very hot.

Tracy
Was this
answer
helpful?
Yes
No
+1
Thursday, December 4th, 2008 AT 7:43 PM
Tiny
JASONRAY
  • MEMBER
You can have the AC on and, at the same time, have the temp. Set to HOT. So, YES, you can have them both on at the same time. In your first post, you mentioned that the AC was cycling too much. If it's cycling pretty fast, that usually means that the system is low on freon. The low pressure switch is turning it off when it gets to a low pressure condition. OR. The HIGH side could be 'pegging' out and the same thing could happen. If the orfice is stopped up, when the compressor engages, the high side will increase pressure quickly and the HIGH pressure switch will cut it off. You'll need to connect a set of AC guages to varify.
I just read up on this system. The temp. Is controlled by an electric motor. There are 3 vacuum actuators but NONE of them control the temperature. They control the floor/panel, fresh air/recirc, and panel/defrost. The blend door(temp.) Is controlled by an electric actuator.
The code 02 you mentioned is for EATC connector and blend door actuator. I think we're on to something here. It's telling you that there is a problem with the actuator and that's why you can only get heat out of the vents. Go directly to the actuator. I'm pretty confident that you'll solve your problem by replacing it. First make sure it's plugged in.
You can test it if you like. Find the wires going to the actuator. (Purple and Brown/light green) Apply battery voltage to one wire at a time. The actuator should move in one direction. Change wires and the actuator should move in the opposite direction. If it doesn't, replace it. If it does, repost and let me know and I'll walk you through further diagnosing.
Was this
answer
helpful?
Yes
No
Saturday, December 6th, 2008 AT 10:48 AM
Tiny
TRACY747
  • MEMBER
TO test eatc WHERE ARE THE WIRES UNDER THE HOOD HARNESS, OR JUST UNDER THE DASH?

CAN I APPLY POWER INTO THE HARNESS WIRES IN PARALELL?

Find the wires going to the actuator. (Purple and Brown/light green) Apply battery voltage to one wire at a time.

The actuator should move in one direction. Change wires and the actuator should move in the opposite direction
Was this
answer
helpful?
Yes
No
Saturday, December 6th, 2008 AT 11:27 AM
Tiny
JASONRAY
  • MEMBER
They will be under the dash. Maybe behind the glove box, or on the bottom of the evap case on the passenger side. It may be easier to pull the control head out and find the wires there. Don't disconnect anything. Just find the wire, pierce the insulation and apply voltage and see if the actuator moves. I use a "POWER PROBE" but if you don't have one, you'll have to make a jumper connected to battery voltage. Be careful not to arc the wire to ground. In fact, if you have to build a jumper, it would be best to include an 'inline' fuse in it just in case you touch it to ground. We don't want a melt down.
Was this
answer
helpful?
Yes
No
Saturday, December 13th, 2008 AT 6:05 PM

Please login or register to post a reply.

Recommended Guides