GEN I - Understanding Climate Control System - No Heat Information

[RigsLS]

2000-2004 Service Information



SECTION 412-00: - Climate Control System - General Information


Dual Automatic Temperature Control (DATC) Module Description

The DATC system automatically maintains a selected temperature for vehicle interior comfort and regulates the volume of airflow between the instrument panel registers, floor ducts, windshield defroster nozzle, and side window demisters. The system will automatically select between fresh and recirculated air with an optional manual override. The DATC system will also include a manual A/C override, blower speed override, and airflow direction overrides.

The dual temperature zone feature provides the driver and the front seat passenger with their own independent temperature set points. The DATC system provides both the driver and front seat passenger with their selected temperature for interior comfort. In situations where the difference between the driver and the front seat passenger set points are very large, the DATC will tend to favor the driver's setting and make the front seat passenger as comfortable as possible.

The driver and front seat passenger will not have independent air distribution mode or fan controls so the system is dual temperature only. In some cases the passenger temperature set point may influence the air distribution mode or blower speed in automatic mode.


System Air Flow

AUTO


When AUTO is selected:

• The temperature control setting(s) are manually set to the desired setting(s).
• The air inlet door actuator is automatically controlled by the DATC module, based on the temperature setting(s), but can be manually overridden by selecting the recirculation button.
• The panel door, floor door, defrost door and cold air bypass door actuators are automatically controlled by the DATC module based on the temperature setting(s), but can be manually overridden by selecting any of the air distribution buttons
• The dual coolant control valve is automatically controlled by the DATC module based on the temperature setting(s).
• The A/C compressor is automatically controlled by the DATC module based on the temperature setting(s), but can be manually overridden by selecting the A/C button. The A/C compressor will not operate if the outside temperature is lower than approximately 2°C (35°F).
• The blower motor is on. The blower motor speed is automatically controlled by the DATC module based on the temperature setting(s), but can be manually overridden by adjusting the blower speed rocker button.

OFF


When OFF is selected:

• The air inlet door actuator positions the air inlet door to close off outside air from entering the passenger compartment.
• The floor door actuator positions the floor door in the open position, and the panel door actuator, defrost door actuator, and cold air bypass door actuator position the panel door, defrost door, and cold air bypass door in the closed positions. This closes off airflow to the defrost duct, the side window demisters, the floor duct and the instrument panel A/C registers.
• The dual coolant control valve is in the closed position, preventing the flow of hot coolant to the heater core.
• The blower motor is off.

PANEL


When PANEL is selected:

• The Recirc request button is enabled. If the Recirc request button is selected (indicator on), the air inlet door actuator positions the air inlet door to close off outside air from entering the passenger compartment. If the Recirc request button is not selected (indicator off), the air inlet door actuator positions the air inlet door to admit only outside air into the passenger compartment.
• The panel door actuator positions the panel door in the open position and the floor door and defrost door actuators position the floor door and defrost door in the closed position, directing airflow to the instrument panel A/C registers. The cold air bypass door actuator is automatically controlled by the DATC module based on the temperature setting(s).
• The dual coolant control valve is automatically controlled by the DATC module based on the temperature setting(s).
• The A/C request button is enabled. When the A/C request button is selected (indicator on), the A/C compressor will operate if the outside air temperature is above approximately 2°C (35°F). When the A/C request button is not selected (indicator off), the A/C compressor will not operate and the air cannot be cooled below the outside temperature
• The blower motor is on.

PANEL/FLOOR


When PANEL/FLOOR is selected:

• The Recirc request button is enabled. If the Recirc request button is selected (indicator on), the air inlet door actuator positions the air inlet door as to close off outside air from entering the passenger compartment. If the Recirc request button is not selected (indicator off), the air inlet door actuator positions the air inlet door to admit only outside air into the passenger compartment.
• The panel door and floor door actuators position the panel door and floor door in the open position and the defrost door actuator positions the defrost door in the closed position, directing airflow to the instrument panel A/C registers and the floor duct. The cold air bypass door actuator is automatically controlled by the DATC module based on the temperature setting(s).
• The dual coolant control valve is automatically controlled by the DATC module based on the temperature setting(s).
• The A/C request button is enabled. When the A/C request button is selected (indicator on), the A/C compressor will operate if the outside air temperature is above approximately 2°C (35°F). When the A/C request button is not selected (indicator off), the A/C compressor will not operate and the air cannot be cooled below the outside temperature.
• The blower motor is on.

FLOOR


When FLOOR is selected:

• The Recirc request button is enabled. If the Recirc request button is selected (indicator on), the air inlet door actuator positions the air inlet door to close off outside air from entering the passenger compartment. If the Recirc request button is not selected (indicator off), the air inlet door actuator positions the air inlet door as to admit only outside air into the passenger compartment. The DATC will automatically revert to the outside air position after approximately 1 to 4 minutes to prevent window fogging.
• The floor door actuator positions the floor door in the open position and the panel door and defrost door actuators position the panel door and defrost door in the closed position, directing airflow to the floor duct. A small amount of airflow from the outboard instrument panel A/C registers will be present. The cold air bypass door actuator is automatically controlled by the DATC module based on the temperature setting(s).
• The dual coolant control valve is automatically controlled by the DATC module based on the temperature settings.
• The A/C request button is enabled. When the A/C request button is selected (indicator on), the A/C compressor will operate if the outside air temperature is above approximately 2°C (35°F). When the A/C request button is not selected (indicator off), the A/C compressor will not operate and the air cannot be cooled below the outside temperature.
• The blower motor is on.

FLOOR/DEFROST


When FLOOR/DEFROST is selected:

• The Recirc request button is enabled. If the Recirc request button is selected (indicator on), the air inlet door actuator positions the air inlet door to close off outside air from entering the passenger compartment. If the Recirc request button is not selected (indicator off), the air inlet door actuator positions the air inlet door as to admit only outside air into the passenger compartment. The DATC will automatically revert to the outside air position after approximately 1 to 4 minutes to prevent window fogging.
• The floor door and defrost door actuators position the floor door and defrost door in the open position and the panel door actuator positions the panel door in the closed position, directing airflow to the floor duct, the windshield defroster ducts, and the side window demisters. A small amount of airflow from the outboard instrument panel A/C registers will be present. The cold air bypass door actuator is automatically controlled by the DATC module based on the temperature setting(s).
• The dual coolant control valve is automatically controlled by the DATC module based on the temperature settings.
• The A/C request button is enabled. When the A/C request button is selected (indicator on), the A/C compressor will operate if the outside air temperature is above approximately 2°C (35°F). When the A/C request button is not selected (indicator off), the A/C compressor will not operate and the air cannot be cooled below the outside temperature
• The blower motor is on.

DEFROST


When DEFROST is selected:

• The Recirc request button is disabled. The air inlet door actuator positions the air inlet door to admit only outside air into the passenger compartment.
• The defrost door actuator positions the defrost door in the open position and the panel door, floor door, and cold air bypass door actuators position the panel door, floor door, and cold air bypass door in the closed position, directing airflow to the windshield defroster ducts and the side window demisters. A small amount of airflow from the outboard instrument panel A/C registers will be present
• The dual coolant control valve is automatically controlled by the DATC module based on the temperature settings.
• The A/C request button is disabled. To reduce fogging, the A/C compressor will operate if the outside air temperature is above approximately 2°C (35°F).
• The blower motor is on

Climate Control System Electrical Components—Directly Linked to DATC Module






Climate Control System Components — J1850 Communications Network (SCP) Linked

 

[RigsLS]

Specific extract for GEN I 2001 V8 w/ NO HEAT ISSUE.

No Heat - Immediate quick check.


Operating temperature - Bring vehicle up to normal warmed up idle temp.

- Verify on point check no visual coolant leaks.

- Check heater hoses going in at firewall.

Caution: hot temperatures.



Is there heat going through the coolant lines to the interior of the LS cabin ?

abstract joegr

http://www.lincolnvscadillac.com/showthread.php?t=68797

No heat at idle could be a failed aux pump.

No heat at anytime could be -

1. Air in the cooling system. On gen I that is usually due to a cracked degas tank. (They crack just as much on gen II, but gen II has other parts that crack a lot too.)
2. The filter screen in the upper radiator hose where it tees off to the DCCV is clogged.
3. The DCCV is clogged or stuck closed.
4. The cold-air bypass door is stuck at the bypass position (you should have gotten a fault code for this).


Warm the engine up and turn the climate control to 90.
Wait a minute and then check the three heater hoses near the firewall.

If they are really hot, then it might be the bypass door.
If they are cool or barely warm, then it's 1, 2, or 3 above.

abstract joegr

http://www.lincolnvscadillac.com/showthread.php?t=69288

Here are some possibilities to look at:

1. Trapped air in the cooling system. Make sure you follow the correct air bleed procedure every time you open the cooling system.
Check your degas bottle. If it's cracked and/or the metal tube inside has come loose, then you will never get all the air out.

2. Thermostat.

3. The upper radiator hose has a plastic screen in it where it tees off to the DCCV. This may be clogged.

4. The heater cores may be clogged.




Setting the control to 90 causes it to go to max heat no matter what its sensors read.
Unplugging the DCCV eliminates the control ability to set the heat level anyway.

One of the following issues:

1. Coolant is too cold. What is the coolant temperature?

2. Little to no flow of coolant through the heater cores. (Clogged, trapped air, DCCV)

3. The cold air bypass door is stuck in the bypass position. (This should have given a 1265 error)





Inspection and Verification


- - - If there is heat going through to the interior heater core ~ door actuators operational.



Operate the climate control system to duplicate the condition.

Function settings on DATC responsive ?

Airflow alters when different modes selected, door actuator actions can be heard ?

Temperature is responsive with selection ?





Dual Electronic Automatic Temperature Control (DATC) Module Diagnostic Trouble Codes—DTCs

If using the scan tool or front panel diagnostics to check for DATC DTCs:

• Check continuous DTCs
• Run DATC self-test. Refer to Front Panel DATC Self-Test (On-demand Diagnostic Trouble Codes — DTCs).

General information:

• If the DTC is continuous only and does not appear in the self-test, this indicates an intermittent fault condition, such as a poor wiring connection or a loose terminal. If the DATC does not appear after running the self-test it may also indicate that the DTC may no longer exist.
• If the DTC is continuous and appears in the self-test, this indicates a hard fault. A hard fault suggests a permanent wiring failure, disconnected connector or component failure.

Front Panel DATC Module Self-Test (On-demand Diagnostic Trouble Codes—DTCs)

On-demand DTCs are those that are reported by an ECU when a failure is detected while executing a diagnostic test. For the DATC module this means that all faults (hard) that occur while the module is conducting a self-test shall be reported as an on-demand DTC.

• The DATC module self-test will not detect concerns associated with data link messages such as engine coolant temperature or vehicle speed signals. The scan tool must be used to retrieve these concerns
• The vehicle interior temperature should be between 0-32°C (32-90°F) when carrying out the self-test. If the temperatures are not within the specified ranges, false temperature sensor DTCs may be displayed.

The DATC module self-test through the front panel display

• can be initiated at any time. Normal operation of the system stops when the self-test is activated
• is entered by pressing the OFF and FLOOR buttons simultaneously and then pressing the AUTO button within two seconds. The display will show counts of 1 to 25 in the center of the display window. Record all DTCs displayed
• concludes by reporting all on-demand DTCs. Follow the diagnostics procedure given under ACTION in the DTC index for each DTC given.
• reports individual on-demand DTCs as four-digit DTCs (less the alpha character).
• will calibrate all the mode doors and check all analog inputs. The DATC module will only report on-demand (hard) faults that occurred while the DATC module was conducting its self-test.
• will light all control panel display segments if no faults are detected.
• will report individual on-demand DTCs without the °C symbol lit.

To exit the self-test, press any button.
This will clear all on-demand codes from the DATC module memory. If no button is pushed DTCs will continue to be displayed.



Upon exit from the self-test the DATC module returns to operational status.
The DATC module executes a hard (cold boot) reset which places the DATC system in the OFF mode.

Always exit the self-test before powering the system down (system turned OFF).



Diagnostic Trouble Code Index


Powertrain Control Module (PCM) Diagnostic Trouble Code (DTC) Index




Dual Electronic Automatic Temperature Control (DATC) Module Diagnostic Trouble Code (DTC) Index









If a condition exists but no DTCs appear during the self-test .... :Bang

 

[RigsLS]

Low heat, No heat, some heat with higher revs

pinpoint test H: Insufficient, erratic, or no heat

 

[2002_lincolnLS]

See if Rollin can add it to the sticky I made, i can't make edits any longer

 

[G-RELL]

NO MORE STICKES... or someone make one thread to hold ALL STICKY's... soon the whole page will be "stickied" and I CANT TAKE IT ANYMORE!!!!!!!!!!!!!! AHHHHHHHHH...sorry

 

[2002_lincolnLS]

NO MORE STICKES... or someone make one thread to hold ALL STICKY's... soon the whole page will be "stickied" and I CANT TAKE IT ANYMORE!!!!!!!!!!!!!! AHHHHHHHHH...sorry

no I mean add this to the existing sticky I have put a link to it with the title like to others to quickly find it

 

[01LS3.9]

Where is the dccv fuse?

 

[RigsLS]

Where is the dccv fuse?

DCCV

DCCV Fuse. Check it!

http://www.lincolnvscadillac.com/showthread.php?t=75655




.. but it's actually listed as the A/C Clutch.

 

[01LS3.9]

Will do. Thanks. If I wanted to unplug the DCCV, where would I look to do it? Does anyone have pics?

 

[RigsLS]

I'm focusing my "no-heat, not enough heat, some heat at higher revs" issues
on low coolant, air in system leak in system, possibly plugged.

The DATC checks all out and is fully functional as intended.


Ordering new OEM parts,

DCCV (18495)
Auxiliary coolant flow pump (18D473)

Degas Bottle also.

~ checking for leaks.

 

[RigsLS]

Will do. Thanks. If I wanted to unplug the DCCV, where would I look to do it? Does anyone have pics?

Bunch o' pics for ya from Google ... lincoln ls dual coolant control valve

by unplugging the DCCV, you are doing the same as cranking the max heat setting to 90F.

#4 is the Auxiliary coolant flow pump P/N 18D473 (3.9L only)
#5 is the Dual Coolant Control Valve P/N 18495

 

[RigsLS]

Search: "dccv" site:http://www.lincolnvscadillac.com/

 

[01LS3.9]

This was REALLY helpful. Thanks, BigRig!

 

[01LS3.9]

by unplugging the DCCV, you are doing the same as cranking the max heat setting to 90F.

#4 is the Auxiliary coolant flow pump P/N 18D473 (3.9L only)
#5 is the Dual Coolant Control Valve P/N 18495

Right. But if the DCCV is no good and is causing the lack of heat, then I will at least have heat, right?

 

[joegr]

Right. But if the DCCV is no good and is causing the lack of heat, then I will at least have heat, right?

If the DCCV is the problem and you unplug it, you still won't have heat.

The only thing that unplugging it would tell you would be if you did get heat with it unplugged, you would know that the DCCV was good and the DATC or one of its sensors was bad.

 

[01LS3.9]

Oh. Ok. Thanks, joe.

 

[RigsLS]

yeah, with mine today. it doesn't restore heat at low idle by disconnecting.
I'm waiting on parts now. Sure the DCCV and Auxiliary pump are faulty.
Can't get the Engine fill cap off. It's stuck on real good.

 

[RigsLS]

Wondering if you guys can give me your input on this.

I got pretty frustrated today with it all. Too much reading and not enough fixing.
I need parts, I know that, it's not going to fix itself by reading or staring at it.

However,

My problem:
Little to no heat, not enough heat, no heat at idle. not leaking coolant, not overheating.

tested so far,

1) DATC seems fully functional, performs self test, no DTC's. able to adjust everything,
with car reving, some heat, and able to adjust temp to cold and back to hot (warm) again via DATC. all doors (modes) seem to function correctly.

2) Hoses going through firewall to heater core, warm but not nearly hot, easily able to squeeze hoses, including rad hoses without much resistance, seems empty.

3) unplugging the DCCV does not provide full hot heat at vents.

~ Added coolant to the Degas Bottle, was low towards the bottom.

~ not able to bleed much, can't get the Engine fill cap of on this 3.9L, worried about breaking it. (plastic)

Operating temperature, opening the drain valve tube near the degas bottle doesn't do much.

~ Coolant stays to the point where I filled it up to after cool down.


- - - -

Re&Re DCCV & Aux pump, refill system and bleed ?

Engine fill cap stuck on ?

DCCV & Aux pump work mostly done from underneath ?


Also, would it be best to go get a flush before or after new parts or both ?

 

[LSter]

BigRig, do you have the diagnostic codes for the DATC for the Gen II with the heated/cooled seats? If so, can you PM them to me or post them?

 

[RigsLS]

oh and the DCCV was already causing problems this summer with the warm air out the passenger side during A/C issue.

 

[RigsLS]

BigRig, do you have the diagnostic codes for the DATC for the Gen II with the heated/cooled seats? If so, can you PM them to me or post them?

No I don't, but for GEN II's same manual online @ http://deneau.info/ls/

 

[joegr]

BigRig, do you have the diagnostic codes for the DATC for the Gen II with the heated/cooled seats? If so, can you PM them to me or post them?

Gen II DATC diagnostics are here:
http://deneau.info/ls/s6x~us~en~file=s6xc0003.htm~gen~ref.htm
Note that they do not include the heated/cooled seats

Codes for the heated/cooled seats:
http://deneau.info/ls/s6x~us~en~file=s6x1a003.htm~gen~ref.htm

 

[NickT88LSC]

Wondering if you guys can give me your input on this.

I got pretty frustrated today with it all. Too much reading and not enough fixing.
I need parts, I know that, it's not going to fix itself by reading or staring at it.

However,

My problem:
Little to no heat, not enough heat, no heat at idle. not leaking coolant, not overheating.



tested so far,

1) DATC seems fully functional, performs self test, no DTC's. able to adjust everything,
with car reving, some heat, and able to adjust temp to cold and back to hot (warm) again via DATC. all doors (modes) seem to function correctly.

2) Hoses going through firewall to heater core, warm but not nearly hot, easily able to squeeze hoses, including rad hoses without much resistance, seems empty.

3) unplugging the DCCV does not provide full hot heat at vents.

~ Added coolant to the Degas Bottle, was low towards the bottom.

~ not able to bleed much, can't get the Engine fill cap of on this 3.9L, worried about breaking it. (plastic)

Operating temperature, opening the drain valve tube near the degas bottle doesn't do much.

~ Coolant stays to the point where I filled it up to after cool down.


- - - -

Re&Re DCCV & Aux pump, refill system and bleed ?

Engine fill cap stuck on ?

DCCV & Aux pump work mostly done from underneath ?


Also, would it be best to go get a flush before or after new parts or both ?

I have same with my car now that it is cold out, heat gets luke warm at best in my car, I have noticed with mine though it struggles to get engine temperature up especially on the highway, at highway speeds in this cold weather engine temp is at 1/4, local driving it will go to 1/2 but takes a long time. No codes in my system either, I am going to change my thermostat first. BTW, that plastic engine fill cap I took off the other day and when I put it back on coolant was coming out where allen key hole is, had to order me a new one, delicate piece, new one I tightened by hand, top of cap says tighten to 9 nm, that is not a lot.

 

[RigsLS]

If the DCCV is the problem and you unplug it, you still won't have heat.

The only thing that unplugging it would tell you would be if you did get heat with it unplugged, you would know that the DCCV was good and the DATC or one of its sensors was bad.

Joegr ?

Knowing that my DCCV during the summer gave me warmer air from passenger vent when in A/C mode, (driver side cool) "and currently" during higher revs able to get some heat, while able to reduce heat to cold with the DATC, it would be safe to assume the DCCV is somewhat still working but the Auxiliary coolant pump is not working getting enough hot fluids to the heater core.

Possible also still air in system ?

Pretty safe bet to just replace both and refill system ?

 

[RigsLS]

Auxiliary Coolant Flow Pump

~ The Auxiliary coolant flow pump is electrically driven and provides increased coolant flow during low engine speed operation.
~ The pump is also used to circulate coolant after the engine is turned off under certain conditions. (???)

#4 is the Auxiliary coolant flow pump P/N 18D473 (3.9L only)


Removal and Installation

1. Disconnect the battery ground cable. For additional information, refer to Section 414-01
2. Drain the radiator. For additional information, refer to Section 303-03
3. Disconnect the connector
   
4. Remove the two auxiliary coolant pump to fan shroud bolts
   
5. Disconnect the hoses and remove the pump
   
6. To install, reverse the removal procedure
   • Make sure that the heater hoses are installed in the correct position.
   • Lubricate the coolant hoses with MERPOL® meeting Ford specification ESE-M99B144-B or plain water only, if needed.
   • Check for correct hose installation by verifying DATC system operation.

Port

1 - Inlet from engine
2 - Outlet to coolant valve​