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Sorry all, it's a new car and I finally have some time off, if you can tell. Here's the latest thing on my list to fix. Here it goes.
The climate control constantly blows 95 degree air at its coldest setting. It blows 140 at its hottest setting and with the A/C on it gets down to 55. Its 70 outside so the question is, why is it always blowing at 95 on the lowest dial settings? I'd figure that it should be close to outside temps.
Both drivers and passengers temps are the same. My guess is the duovalve is slightly stuck open but before I tear into it I wanted to get some feedback from the members. Thanks.
Sorry all, it's a new car and I finally have some time off, if you can tell. Here's the latest thing on my list to fix. Here it goes.
The climate control constantly blows 95 degree air at its coldest setting. It blows 140 at its hottest setting and with the A/C on it gets down to 55. Its 70 outside so the question is, why is it always blowing at 95 on the lowest dial settings? I'd figure that it should be close to outside temps.
Both drivers and passengers temps are the same. My guess is the duovalve is slightly stuck open but before I tear into it I wanted to get some feedback from the members. Thanks.
The valves under the hood are not working, does it blow the same on both passenger and driver sides of the car. The valves should shut down when the temperature is dialed down with the AC on.
Yup, both passenger and driver are the same. I figured it was the duovalve but I wanted to check with others before I cracked it open. I guess I'll be taking it apart in the morning.
Yup, both passenger and driver are the same. I figured it was the duovalve but I wanted to check with others before I cracked it open. I guess I'll be taking it apart in the morning.
It could well be the controls that are at fault. Do a search on the forum.
Whelp, I'm guessing that it wasn't the duovalve that was at fault because I took it apart and it looked very clean. I wiped down the parts and reassembled. I'll keep an eye on it to see if anything has changed. If not, on to the controls themselves.
Whelp, I'm guessing that it wasn't the duovalve that was at fault because I took it apart and it looked very clean. I wiped down the parts and reassembled. I'll keep an eye on it to see if anything has changed. If not, on to the controls themselves.
Thanks onehundred80. I read thru the post but it seems like there was more than one working theory. I'll check the blend door and vacuum line next. At the moment, things seem to be working. I'll give it a couple of days to see if my valve clean was the remedy.
The control head has a systemic problem with these cars. If BOTH sides are dumping heat into the cabin when not asked for, I see a minimum of two potential issues here. One, the duovalves may not be adequately commanded to 'close', and the blend door may not be closing off the hot coils in the cabin. Turn both temp ***** to one detent from max cool, and feel the individual lines at the firewall. If the lines are hot as all gitgo, then the control head is not sending a full signal to the valves to close (after car is fully warmed up). I postulate the blend doors never do seal 100% so that may not be your issue. Full hot heater coils (drivers side and passenger side) will leak heat into the cabin even if the blend doors are working correctly. There is a fix offered to the control head, that involves taking it apart and 'reconnecting' intermittent pins on the PC boards (that either vibrate loose of build up oxidation on them until vibration reconnects it). This definitely explains the 'working now' but 'not working again' some time later. Check if the heater lines are extremely hot first, that might help narrow down if the control head is the problem.
Of course, you made sure the duovalves coils are not burned out, right? Unplug them and check the continuity with a simple ohm meter. After that, you can test if the head is sending a signal to them. You'll see a pulse (voltmeter jumping) according to the individual cabin dial settings. With both set to full cool, you should see each valves coil having constant power to them (might be a minor 'off' in a rhythmic pattern to keep the coolant moving). Remember, these valves are set up to failsafe in the flow (open) position. This means when the system has a problem in cold weather, you'll have heat through the coils.
Finally, you have to make sure you allow the car to fully cool down before you try to troubleshoot different things UNLESS you know things like if you disconnect the duovalves the flow will make the coils hot (no signal to close them). If you think having the car off while the system is hot (to check the coil continuity), you may find the temperature differences caused a thermal flow to occur causing the coils to be very hot and influencing your results.
The control head has a systemic problem with these cars. If BOTH sides are dumping heat into the cabin when not asked for, I see a minimum of two potential issues here. One, the duovalves may not be adequately commanded to 'close', and the blend door may not be closing off the hot coils in the cabin. Turn both temp ***** to one detent from max cool, and feel the individual lines at the firewall. If the lines are hot as all gitgo, then the control head is not sending a full signal to the valves to close (after car is fully warmed up). I postulate the blend doors never do seal 100% so that may not be your issue. Full hot heater coils (drivers side and passenger side) will leak heat into the cabin even if the blend doors are working correctly. There is a fix offered to the control head, that involves taking it apart and 'reconnecting' intermittent pins on the PC boards (that either vibrate loose of build up oxidation on them until vibration reconnects it). This definitely explains the 'working now' but 'not working again' some time later. Check if the heater lines are extremely hot first, that might help narrow down if the control head is the problem.
Of course, you made sure the duovalves coils are not burned out, right? Unplug them and check the continuity with a simple ohm meter. After that, you can test if the head is sending a signal to them. You'll see a pulse (voltmeter jumping) according to the individual cabin dial settings. With both set to full cool, you should see each valves coil having constant power to them (might be a minor 'off' in a rhythmic pattern to keep the coolant moving). Remember, these valves are set up to failsafe in the flow (open) position. This means when the system has a problem in cold weather, you'll have heat through the coils.
Finally, you have to make sure you allow the car to fully cool down before you try to troubleshoot different things UNLESS you know things like if you disconnect the duovalves the flow will make the coils hot (no signal to close them). If you think having the car off while the system is hot (to check the coil continuity), you may find the temperature differences caused a thermal flow to occur causing the coils to be very hot and influencing your results.
.
I read that the problem was solved at the moment.
Last edited by onehundred80; 12-22-2016 at 07:07 PM.
Well, cleaning the duo valves didn't have an effect so back to the drawing board.
Originally Posted by GraphiteGhost
: Turn both temp ***** to one detent from max cool, and feel the individual lines at the firewall. If the lines are hot as all gitgo, then the control head is not sending a full signal to the valves to close (after car is fully warmed up).
They are warm/hot to the touch but not so hot that I couldn't hold them.
Originally Posted by GraphiteGhost
: Of course, you made sure the duovalves coils are not burned out, right? Unplug them and check the continuity with a simple ohm meter.
I did. Both sides are coming in at 25.5.
Originally Posted by GraphiteGhost
: After that, you can test if the head is sending a signal to them. You'll see a pulse (voltmeter jumping) according to the individual cabin dial settings.
I did that as well. Full cold is showing 12v across both terminals and full heat is 7.8 across both terminals as well.
Next stop is the blend door then the controls themselves next.
In my humble opinion (and having three SRT6s, I've been there / done that several times) . . . in spite of the fact that you tried to clean and reassemble the dual control valves, I still believe that is where your problem can be found. I have tried the cleaning and reassembly more than once but usually end up replacing the dual valve assembly. The tiny wires to the coils corrode or break and the coil(s) fail. The default is HEAT instead of COLD. You can get a used pair of valves on E-Bay and just swap out the upper section. That should fix your problem.
In my humble opinion (and having three SRT6s, I've been there / done that several times) . . . in spite of the fact that you tried to clean and reassemble the dual control valves, I still believe that is where your problem can be found. I have tried the cleaning and reassembly more than once but usually end up replacing the dual valve assembly. The tiny wires to the coils corrode or break and the coil(s) fail. The default is HEAT instead of COLD. You can get a used pair of valves on E-Bay and just swap out the upper section. That should fix your problem.
RED DOG, he has posted the symptoms and checked the coils already, they are not stuck open and the coils are showing continuity. Swampotter, the slight warm lines are a good sign, now lets turn the dials to max cool setting, turn on the fan, and start the car (after the car cooled down completely cold). Don't push the A/C button, leave it off (no need to), wait until the car is warmed up and feel the zone lines (the two lines going to the duovalves where they exit the firewall behind the passenger side shield. Those two lines should not be hot. Without changing any settings, feel those valves while the car is running (based on the zone temp dial set to max cool and fan on), you should not feel the 'thump' of the valves. If you move the temp dials to any other setting on either zone, and they are cycling (it is a pulse, they cycle on/off rhythmically), that respective 'zone valve' will pulse and the line associated with that zone will get progressively hot. Unfortunately it takes time to determine if the valves are shutting off 100% because it takes time to 'bleed' off the heat after they circulate hot coolant (which is why we want START with the dials first set to max cool with fan running, if they are 'leaking' internally one or both will get hot). Feel those two valve bodies (the duovalve) while checking the two zone lines at the firewall behind that shield, make sure those two valves are not 'pulsing' at all (you can feel when they do). If they are, it is getting a signal to cycle and no replacing of the valves will fix this. One MUST remember that this issue is intermittent, which again leads me to the systemic problem with the control head. Throwing parts at it (especially USED parts) is not a sound program to follow. I believe Dave (180) lists that control head .pdf in his huge list of help fixes, that fix costs almost nothing, and may solve this intermittent problem. Lets keep focus on determining if the valves are shutting off 100% when not commanded to open, ok?
Originally Posted by onehundred80
If you start the car when the engine is cold there should be no heat in these hoses with the heat dialed OFF. That is what I see.
If the whole system failed and you start the car cold, you'll have no heat, period. Not sure what you meant, am having a senior moment here trying to understand what your trying to say.
If the whole system failed and you start the car cold, you'll have no heat, period. Not sure what you meant, am having a senior moment here trying to understand what your trying to say.
.
Who said the whole system has failed?
Your second and third sentences say exactly what I said. What is in my reply makes sense when you couple it to the OPs statement that I quote. You cannot take what I said on its own.
Who said the whole system has failed?
Your second and third sentences say exactly what I said. What is in my reply makes sense when you couple it to the OPs statement that I quote. You cannot take what I said on its own.
I didn't, I made a point, it went over your head. Just like your post went over my head, Relax. Thing is if the car is cold and working 100% (taking your post exactly as written) nothing is hot, get it? His reply to me " They are warm/hot to the touch but not so hot that I couldn't hold them.
" was referencing my post that to check systematically I asked him to set the dials to ONE click off max cold. That is why the lines were warm but not hot. I needed to know that before we moved them to max cold and then check again.
.
Last edited by GraphiteGhost; 12-23-2016 at 11:34 AM.
Ok fellas, I feel like the princess at a school prom. Love all the ideas so keep them coming. Here's today's efforts before I shut it down for Holidays.
1) it's currently 61 outside. I fired up the car and the temps from all vents at the coldest setting (no a/c) is blowing 53 degrees (I'm assuming it's because the antifreeze is colder because of overnight temps). Hoses at the firewall are cold, valves are cold, hose feeding valve is cold.
2) bringing car to temp. After 5 minutes of idle, hoses are all cold, temp in cabin is 58 degrees. The valves are warm. 80 degrees according to my laser gauge. (I find this odd)
3) 15 minutes in, interior temps now 58, surface temp of the valves are 104, hose feeding the valve is 63 and the hoses at the firewall are 62.
4) drives side heat now full blast, 115 and climbing in the cabin, passenger 80 and climbing. Drivers valve 125, passenger 113. Feeder hose 130, drives hose at firewall 130, passenger 85.
5) both sides full heat. 130 out both vents, both valves about 130 as well.
6) all settings at coldest (no a/c) and waited 10 minutes at full blast. Cabin air is coming out at 70, the drives side valve is a blistering 150 and the passenger valve is 125.
I didn't hear any opening and closing of valves with the engine running though I can feel antifreeze flowing thru the feeder hose. The valves do cycle with the engine off but not rhythmically.
Ok fellas, I feel like the princess at a school prom. Love all the ideas so keep them coming. Here's today's efforts before I shut it down for Holidays.
1) it's currently 61 outside. I fired up the car and the temps from all vents at the coldest setting (no a/c) is blowing 53 degrees (I'm assuming it's because the antifreeze is colder because of overnight temps). Hoses at the firewall are cold, valves are cold, hose feeding valve is cold.
2) bringing car to temp. After 5 minutes of idle, hoses are all cold, temp in cabin is 58 degrees. The valves are warm. 80 degrees according to my laser gauge. (I find this odd)
3) 15 minutes in, interior temps now 58, surface temp of the valves are 104, hose feeding the valve is 63 and the hoses at the firewall are 62.
4) drives side heat now full blast, 115 and climbing in the cabin, passenger 80 and climbing. Drivers valve 125, passenger 113. Feeder hose 130, drives hose at firewall 130, passenger 85.
5) both sides full heat. 130 out both vents, both valves about 130 as well.
6) all settings at coldest (no a/c) and waited 10 minutes at full blast. Cabin air is coming out at 70, the drives side valve is a blistering 150 and the passenger valve is 125.
I didn't hear any opening and closing of valves with the engine running though I can feel antifreeze flowing thru the feeder hose. The valves do cycle with the engine off but not rhythmically.
As it sits, it looks like the valves are operating normally (good thing it worked correctly during these tests), as having it malfunction skewers test results. Remember, the valves are powered on when closed (max cool dials), so the valve tops will warm up since the coils are energized/heating up (your reference to them being @ 80 degrees, and being odd). The key note is, both hoses are cool and the cabin is cool. If you were to again throttle the dials, then the hoses (respective to the zone adjusted) will heat up. Also, remember you noted the valve tops were at 130 along with the hoses, all that means is the heat from the coolant made everything hot after flowing through the lines during the heat selections. Remember also, you would not have heard the valves open/close, you can just 'feel' the tops of the valves as they cycle. An example of this would be set the dials to mid level, while the car/system hot & running, just lightly 'cup' one, or both valve caps. If you use your free hand, you can also 'feel' the coolant lines as the valves 'surge' when those duovalves cycle. At this stage, your valves seem to be working correctly. This is the case where this intermittent problem gets harder. Did you find that .pdf for the control head fix a member discovered? I was experiencing this type of intermittent problem, but it has been quite a long time since it came back, so I did not do the fix that was offered.
Found it (Thanks to Dave/180 listing all these). Since I could not find it, I downloaded it again. It is attached, and references the member CL770(?). One reason I could not find it (maybe) was the listing as 'Heater/AC Speed Control Repair'. Given the number of pins, and the systemic problems with these heads, I think this 'fix' would correct this specific problem (and most of the) annoying intermittent A/C problems. Good luck with the fix, if you do it. Post back your findings/results? Hope your Christmas is fun, safe, and happy for all!
Found it (Thanks to Dave/180 listing all these). Since I could not find it, I downloaded it again. It is attached, and references the member CL770(?). One reason I could not find it (maybe) was the listing as 'Heater/AC Speed Control Repair'. Given the number of pins, and the systemic problems with these heads, I think this 'fix' would correct this specific problem (and most of the) annoying intermittent A/C problems. Good luck with the fix, if you do it. Post back your findings/results? Hope your Christmas is fun, safe, and happy for all!
It is now renamed 'Heater/AC Fan Speed Control Removal and Repair'.
Removal instructions are added as well. Click to see it.
It is now renamed 'Heater/AC Fan Speed Control Removal and Repair'. Removal instructions are added as well. Click to see it.
Thanks Dave! I'll redownload it and post in my package I have for if/when I do mine. You always support these fixes to the MAXIMUM! Wish you and yours a SAFE Merry Christmas and New Year!
I'm back. I did the Heater/AC Fan Speed Control fix. I've given it a week and although it worked a little better the situation never fully resolved itself. The next step was to check the blend door. I removed the plastic cowl below the windshield and noticed the door was in the closed position. I gave it a little push and it opened. I then turned the car on and started the climate fan. I next hit the Rest button and watched the door close. I then turned off the Rest button however the door stayed closed. I'm assuming it should have opened up to allow fresh air in. Any suggestions?
Climate control blows warm air, A/C is fine
The control head has a systemic problem with these cars. If BOTH sides are dumping heat into the cabin when not asked for, I see a minimum of two potential issues here. One, the duovalves may not be adequately commanded to 'close', and the blend door may not be closing off the hot coils in the cabin. Turn both temp ***** to one detent from max cool, and feel the individual lines at the firewall. If the lines are hot as all gitgo, then the control head is not sending a full signal to the valves to close (after car is fully warmed up). I postulate the blend doors never do seal 100% so that may not be your issue. Full hot heater coils (drivers side and passenger side) will leak heat into the cabin even if the blend doors are working correctly. There is a fix offered to the control head, that involves taking it apart and 'reconnecting' intermittent pins on the PC boards (that either vibrate loose of build up oxidation on them until vibration reconnects it). This definitely explains the 'working now' but 'not working again' some time later. Check if the heater lines are extremely hot first, that might help narrow down if the control head is the problem. 
Of course, you made sure the duovalves coils are not burned out, right? Unplug them and check the continuity with a simple ohm meter. After that, you can test if the head is sending a signal to them. You'll see a pulse (voltmeter jumping) according to the individual cabin dial settings. With both set to full cool, you should see each valves coil having constant power to them (might be a minor 'off' in a rhythmic pattern to keep the coolant moving). Remember, these valves are set up to failsafe in the flow (open) position. This means when the system has a problem in cold weather, you'll have heat through the coils.
As it sits, it looks like the valves are operating normally (good thing it worked correctly during these tests), as having it malfunction skewers test results. Remember, the valves are powered on when closed (max cool dials), so the valve tops will warm up since the coils are energized/heating up (your reference to them being @ 80 degrees, and being odd). The key note is, both hoses are cool and the cabin is cool. If you were to again throttle the dials, then the hoses (respective to the zone adjusted) will heat up. Also, remember you noted the valve tops were at 130 along with the hoses, all that means is the heat from the coolant made everything hot after flowing through the lines during the heat selections. Remember also, you would not have heard the valves open/close, you can just 'feel' the tops of the valves as they cycle. An example of this would be set the dials to mid level, while the car/system hot & running, just lightly 'cup' one, or both valve caps. If you use your free hand, you can also 'feel' the coolant lines as the valves 'surge' when those duovalves cycle. At this stage, your valves seem to be working correctly. This is the case where this intermittent problem gets harder. Did you find that .pdf for the control head fix a member discovered? I was experiencing this type of intermittent problem, but it has been quite a long time since it came back, so I did not do the fix that was offered.