GEN I - Understanding Climate Control System - No Heat Information

[RigsLS]

Item

1 - Clamp #8287
2 - Clamp #8287
3 - Heater hose #18472
4 - Clamp #8287
5 - Heater hose #18N345
6 - Clamp #8287
7 - Heater hose #18472
8 - Dual coolant control valve electrical connector #18C463
9 - Dual coolant control valve bolt
10 - Dual coolant control valve (DCCV) #18495
11 - Clamp #8287
12 - Clamp 8287
13 - Heater hose #18472
14 - Clamp #8287
15 - Heater hose #18472
16 - Auxiliary coolant flow pump electrical connector #18C463
17 - Auxiliary coolant flow pump bolt (2 req'd)
18 - Auxiliary coolant flow pump #18D473

 

[RigsLS]

Dual Coolant Control Valve

The dual coolant control valve regulates the flow of engine coolant to each half of the heater core. Two electric solenoids, which are individually actuated by the dual-zone EATC module, are the control elements. Based on inputs from the dual-zone EATC module, the solenoids cycle open and closed to regulate the coolant flow to the heater core. The solenoids can be cycled at different speeds by the dual-zone EATC module in order to maintain different temperatures for each half of the heater core. Under certain conditions when heating is not required, the dual coolant flow valve will bypass the heater core by closing both solenoids.



Dual coolant control valve (DCCV) #18495


I'm still looking into this but there appears to be some discrepancies back and forth on this DCCV.

In both the GEN I and II workshop manuals, they flip back and forth on referencing it,

1) Dual Coolant Flow Valve

2) Dual Coolant Control Valve


The GEN I instructs you to take it out from underneath the vehicle.
The GEN II wants the Upper rad hose out of the way and then remove DCCV from up top.

I've also seen some DCCV with both 3 or 5 inlet/outlet tubes.

( still trying to get my head around that )

 

[oddball]

The GEN I instructs you to take it out from underneath the vehicle.
The GEN II wants the Upper rad hose out of the way and then remove DCCV from up top.

I've also seen some DCCV with both 3 or 5 inlet/outlet tubes.

( still trying to get my head around that )

Gen I has 5 connections and mounts to the frame rail behind and below the radiator and is accessible from the bottom.
Gen II has 3 connections and mounts to the fan shroud.

 

[RigsLS]

Thanks!

~ this is what happens when you look at two different manuals, why I do that, I do not know.

I'm GEN I specific to my problem and this thread.



UPDATE: there is a discrepancy then !

both GEN I & II manuals show DCCV as P/N 18495

if GEN I has 5 connections and,
GEN II has 3 connections,

one would want to be very careful ordering P/N 18495


unless, I'm still missing something.

 

[RigsLS]

Ah !!!

2R8Z-18495-AA Possibly Gen 2 only.
MOTORCRAFT Part # YG378

XW4Z-18495-AA Possibly Gen 1 only.
MOTORCRAFT Part # YG355

 

[01LS3.9]

What did you do to unplug the DCCV? Did you have to remove anything? Did you reach it from above or below?

 

[RigsLS]

Bump <shrugs> just because.

~ from below.

 

[Leblanc5]

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.

If you replace the DCCV take the old one apart and I'm willing to bet one valve is plugged, corroded and probably pitted. It's from not using the "DUAL" function. Always run it in duel mode and cycle it cold to hot every once in a while. That should keep the valve lubricated and the lines from plugging

 

[joegr]

... It's from not using the "DUAL" function. Always run it in duel mode and cycle it cold to hot every once in a while. That should keep the valve lubricated and the lines from plugging

Sorry, but that's not true at all. Dual or single, both valves still cycle. In dual mode, you can set the temperature you want out of both sides independently. In single mode, both sides are still independently controlled to get the same temperature out of both sides. To get the same temperature out, both valves will still open/close at different times to regulate each side.

Also, it is false to assume that they don't cycle even with the system off. Every time you turn the key off, both valves open fully after several minutes (full heat), otherwise, it would run the battery down. (No power = open, power = closed.) When you start the car with the system cooling or off, the valves are both powered and they both close (full cooling).

They do get plugged and corroded, but it's not from lack of use. They get plugged if you don't change the coolant often enough. They corrode because the internal seals start to leak with time.

The DCCV is a wear part. You'll probably have to replace it every 70K to 150K miles. Some will be longer, and some will be shorter intervals.

 

[Leblanc5]

Sorry, but that's not true at all. Dual or single, both valves still cycle. In dual mode, you can set the temperature you want out of both sides independently. In single mode, both sides are still independently controlled to get the same temperature out of both sides. To get the same temperature out, both valves will still open/close at different times to regulate each side.

Also, it is false to assume that they don't cycle even with the system off. Every time you turn the key off, both valves open fully after several minutes (full heat), otherwise, it would run the battery down. (No power = open, power = closed.) When you start the car with the system cooling or off, the valves are both powered and they both close (full cooling).

They do get plugged and corroded, but it's not from lack of use. They get plugged if you don't change the coolant often enough. They corrode because the internal seals start to leak with time.

The DCCV is a wear part. You'll probably have to replace it every 70K to 150K miles. Some will be longer, and some will be shorter intervals.

I stand corrected sir

 

[AutumnRed]

I'm wondering what the ABS control module has to do with the HVAC system first posted toward the end of the diagrams. Anyone?

 

[joegr]

The ABS module provides vehicle speed information to the various modules. The PCM uses this along with the high side AC pressure to decide what speed to run the engine fan at. There may be some other tie-ins too.

 

[LSE_4_LYFE]

Wow! Awesome info. I'm thinkin dccv on mine. No leaks, new oem coolant bottle. Before I replaced it there was heat wen it was full of coolant. Bottle had big crack so as soon as it leaked out it went cold. Replaced bottle and now I don't have heat. I'll bleed it and I'll get heat. Shut it off then next time I start it again no heat. Another thing is hoses will be hot but coolant coming out of bleeder valve will be cold. Guessin clog but where??

 

[joegr]

... I'll bleed it and I'll get heat. Shut it off then next time I start it again no heat. ...

That's not going to be the DCCV, unless it is leaking. You have the classic symptoms of micro-cracks in the plastic cooling system parts. They aren't big enough to let out a noticeable amount of coolant, but they are enough to let air back in. Everybody resists this, but it's almost always the case with this car. Replace all the plastic cooling system parts, and be done with it.

 

[LSE_4_LYFE]

That's not going to be the DCCV, unless it is leaking. You have the classic symptoms of micro-cracks in the plastic cooling system parts. They aren't big enough to let out a noticeable amount of coolant, but they are enough to let air back in. Everybody resists this, but it's almost always the case with this car. Replace all the plastic cooling system parts, and be done with it.

Ty. I'm workin on doing that. So far thermostat housing and coolant bottle are done. Other than upper and lower radiator hose what else should I replace? I was thinking dccv because when I do have heat it's not the same on driver and passenger side. Once it was warmer on pass side. Next time it switched.

 

[LSE_4_LYFE]

Another important piece of info. LS has 218k miles. None of the parts look that old. I'm sure they've been replaced. Not sure wen so I'm gradually replacing each part. One that was not replaced was coolant bottle as I kno no one ever does. Especially not with OEM one. I don't think dccv was replaced. Hoses do look newer. Car runs fine no overheating or leaks at all while driving. Just no heat. And if I do get heat after bleeding, I'll shut it off and let it sit for a while then on start up I'm back to no heat.

 

[joegr]

... And if I do get heat after bleeding, I'll shut it off and let it sit for a while then on start up I'm back to no heat.

Because air is being sucked in through tiny cracks in the plastic.

 

[RigsLS]

... Everybody resists this, but it's almost always the case with this car. Replace all the plastic cooling system parts, and be done with it.

Yup yup ... after all these years, we still need to promote this.
Had the Tech articles or Sticky's been cleaned up to reflect this we'd not have to mention it as often.

Still a problem to date I see ...
I had offered long time ago to clean that all up and organize it properly ... but ego's prevailed so, f*ck it, not my problem.

 

[LSE_4_LYFE]

Maybe I asked wrong. I understand replace coolant parts. I know plastic pieces. But what non plastic parts should I replace? Dccv, water pump, aux thing I forget exact name. I don't want to buy shit just to buy but if it's best it's best. I've heard those parts but not sure what they do and how to tell if they're gd. Joegr you say dccv is probably not bad unless it's leaking. Where would it be leaking and is that only way to tell it's bad. Also the other parts. I'm planning on doing all new eventually. It will be a project car for my daughter and I. For now just trying to keep it going. Ty for your help and advice.

 

[joegr]

You have a leak. There's no other way that air is getting back in there to block coolant flow. It really is that simple.

What LS do you have? Which generation? Which engine?
I had assumed it was a gen I V8, but you are asking about which parts when you have already been in a pretty good thread on the gen I V8 parts.
Cooling System 3.9L - 1st GEN Lincoln LS w/ PN's
I would add to that thread to check your radiator. The side tanks are plastic, and eventually the front of the passenger side tank cracks near the top.

The "aux thing" is the aux coolant pump. It's by the DCCV. The DCCV is bad if it leaks, if it is stuck open or closed, if it is clogged, or if it has an electrical open or short. The DATC self diagnostics can catch the short or open, but not the other problems.
If you have good heat at idle (right after bleeding, before the air gets sucked in again), then the aux pump is okay (unless it is leaking).
You probably won't see liquid coolant at the leaks, but you could see the stains from dried coolant.

Also note that aftermarket degas bottles tend to be really bad. If you went aftermarket, that could also be the problem.

 

[LSE_4_LYFE]

You have a leak. There's no other way that air is getting back in there to block coolant flow. It really is that simple.

Ty. No aftermarket coolant. Ford OEM only for me. No leaks. Ty for info. And yes it is gen1 v8. 02. Thermostat housing and bottle new. So other parts I need to get will be upper and lower radiator hoses right? And I'll check radiator. Had heard that but not exactly where to check for leaks or cracks. Ty again.

What LS do you have? Which generation? Which engine?
I had assumed it was a gen I V8, but you are asking about which parts when you have already been in a pretty good thread on the gen I V8 parts.
Cooling System 3.9L - 1st GEN Lincoln LS w/ PN's
I would add to that thread to check your radiator. The side tanks are plastic, and eventually the front of the passenger side tank cracks near the top.

The "aux thing" is the aux coolant pump. It's by the DCCV. The DCCV is bad if it leaks, if it is stuck open or closed, if it is clogged, or if it has an electrical open or short. The DATC self diagnostics can catch the short or open, but not the other problems.
If you have good heat at idle (right after bleeding, before the air gets sucked in again), then the aux pump is okay (unless it is leaking).
You probably won't see liquid coolant at the leaks, but you could see the stains from dried coolant.

Also note that aftermarket degas bottles tend to be really bad. If you went aftermarket, that could also be the problem.

 

[LSE_4_LYFE]

When it comes to replacing hoses, is there a big difference between parts store brand dayco, motorcraft or Ford? I know when it comes to coolant bottle there's a huge difference. Lol