Lincoln mark 8, a/c was working, then kept starting and stopping now dead, compressor works, fan wont blow, even on vent or heat....where is the fuse/relay for this or what else could it be?

bad blend or mode damper door motor actuators. is cause (maybe)
we know how to move them by hand motors off (actuators)
hot all the time is blend unless AC compressor is dead.
yes blend doors can jam fully to hot, sure can.,
It needs service, there are other causes.
most of the tests you can not do. or easy.
there are 2 systems here.

• the blower distributor system. (dampers 3 or more0
• or
• the AC R134 loop dead or weak.

what I do is make sure the compressor runs
and if does,
move the blend door by hand (my jeep has built in self test of this)
and by hand I put the damper to evap core only mode and if no cold air now, the loop is bad and I stop here, lots more tests from hear.

or he AC condensate drain is clogged even covering up deeply evap core . blocking is air flow., and super common this and a simple fix.

You might want to try turning the climate control temp settings all the way down. Then turn the system OFF. Disconnect the negative battery terminal and let the car sit for 5 to 10 minutes. When time is up reconnect the battery and then start the car. Turn on the Heat/AC and adjust the temp setting.

Sometimes this works on cars with computer controlled climate control systems.

Good luck.

I noted your question. You said that NOTHING is coming out of the VENT. Do you mean the interior vents normally for heat and air? Does air blow out of your dash defrost vent? Does blower motor work continuously? If so, I suggest that you check fuse panel at driver's door. If you have your owner's guide, look on pages 251 and 252. 251 shows your interior fuses. 252 shows description for Fuse #9 (10A). You have numerous 10A fuses. #9 is the lowest fuse perpendicular to Fuse #10 (15A). If it is blown, you have some sort of resistance in one of 4 things RUN BY THE FUSE. I went to my mechanic and he told me that the Blower Motor Control Resistor behind the glove compartment was bad. I replaced it (125 dollars) and it was not the problem. Check the fuse. Is it blown? Replace and the system may work normally. If it continues to blow please get back to me. If the system works after replacement, please respond.

If the air stops blowing from the vents, the problem is with the blower motor. If it doesn't come on, try slapping the motor with your hand. If it starts when slapped, replace the motor.

Do It Yourself Diagnosis and Repair

Sounds like a vacuum leak.

There is a blender that controls the air flow to go through the heater core for heat, and the evaporator for AC. It very well could be stuck.

You maybe able to try and get it to get unstuck by running the cars AC and switching from heat to AC back and forth and see if it gets unstuck. Just turn it on full blast and go from heat to cool.

If that fails, then you may need to service it. There should be a Lever Marked VENT under the dash, usually by the Brake and other pedals on the Driver's Side. Close the VENT and that will stop the Air from coming in and leave the A/C Blowing through the outlets(Vents).

I also read this online if you have an electronic climate control. "On climate control press off and heat button and let go quickly. Then press automatic. The display will start rotating eventually displaying a code 025,125 , 024 etc. Then press defrost to stop. You may hear blend door operating atb that time. It worked for my climate control."

Yes, the fan motor may be bad, check the fuse, if its blown, the motor may be bad. the fuse is marked HEATER 40 Amps.

Air Suspension Compressor Motor/Vent Solenoid : Lower RH front corner of engine compartment C134
Air Suspension Switch : Rear side of trunk C458
Air Suspension/EVO Steering Module : Behind RH cowl panel, above connector bracket C204, C205
Air Suspension/EVO Test Connector : RH side of engine compartment, top of wheel well C117 Soft Ride Relay : Under center front of package tray C403Hard Ride Relay : Under center rear of package tray C404 sorry could not find compressor rely listed, good luck

Hi - There may be 2 separate problems. On my 1991 Lincoln Town Car, there is a Thermal Blower Lockout sensor that disables the heater from blowing until the engine temperature reaches a specific temperature. This way if you have vent or floor settings and 90 degrees set and it is winter, you won't get blasted with cold air. When the vehicle warms up, the TBL circuit enables the climate control to blow the hot air. If you use the flr/def instead of the floor or vent control, the TBL should not prevent the heater from working even with a cold engine. On my car, the TBL went bad and always prevented hot air from blowing on the floor and vent settings, even when the engine was hot. Another thing to check is a thermal limitor resistor. It is designed to cut off the blower at very hot temperatures, except if the blower fan is in the hi setting.

As far as the A/C is concerned, can you verify if the clutch is engaging or not? A rapid cycling of the clutch is an indication of low freon. If you are absolutely sure that you are fully charged on freon, I think there are 2 possible causes: (1) Bad pressure switch on the accumulator is indicating low freon that is telling the compressor not to work; (2) a blocked orifice tube.

Check the engine temperature sensor, and the cooling fan switch, they both control the fan operation. One or both are not working.