Hi All,
I am new to this forum, although I have followed a number of items as a non Member .
I have basically inherited a 2000 S Type 3L V6 right hand drive ( I live in Australia) and like so many that I have read about, have had a problem with The Dual Climate Control Valve.
I finally bit the bullet and decided to go ahead on change it after checking the Main CC module etc. I have to say, like so many others have previously said, it was the devils own job to carry out and from a purely engineering point of view (I actually am and Engineer) the idea to position this valve in the vehicle, leaves a lot to be desired.

I have a query as I believe something is right, I found the electrical plug which plugs to the top of the dual solenoid assembly on the valve, has a wire (uninsulated and internal in the actual plug top) bridging between the outside pins on either side of the plug. (Refer attached photo)
To my mind this does not seem correct and seems to defeat to purpose of the solenoids operation. My question is , "Should this be there or has someone done this deliberately" and do I remove it before replugging it onto the valve assembly?
Thank You in anticipation of a response - Jeff

 

Welcome to the forum.

That jumper is a hokey "fix". You can safely remove it. I suspect somebody had a control module that had failed on one of the two control circuits. By jumpering between the two contacts, both side of the DCCV would operate from whichever control circuit was still active.

Have you seen this troubleshooting guide?:

https://www.jaguarforums.com/forum/s...ol-how-185002/

You will see some links showing how a bad DCCV can damage the control module, but that is primarily on 2003+ models.

 

Hi kr98664,
Many thanks for your fast response. I will remove the jumper wire and replug to the new Valve assembly.
Perhaps, there is actually a faulty main module, however I have removed it previously prior to changing the DCCV unit and could not see anything obviously wrong with it.
I note your highly detailed troubleshooting guide and will work my way through it if the replacement valve continues to cause issues with the system.
Again, many many thanks. Regards, Jeff

 

This is from memory, oops.

One of my 2 X200 beasts had DCCV issues. Did what you did, said the words the same.

NO CHANGE, called it beer o;clock for a few days.

Fuse #1 (thats the memory bit) is the fuse for that valve, and the Black car was blown, looked 100%, but blown,
New fuse, along with the valve, sweet as.

The X200 rarely gave module issues, that joy is for the X202 onwards.

 

How did you inspect the RCCM or the CCM? With that hack job of bypassing the DCCV you know whoever was in there did that. So the car has had this problem before and was improperly repaired. Can you post a picture of the circuit board?

I would be very suspicious that the prior "repairs" might have taken out the climate control module. Not sure what "main module" your talking about?
Do follow Karl's large and classic troubleshooting thread as it contains all the information you need plus more!

Yes the cars are made to be assembled...once. Then drive it and throw it in the junk yard. Your not suppose to understand how anything works or do any repair work. The car is 25+ years old and should have long ago been discarded.
Welcome to the modern world!

What brand of DCCV did you purchase?
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Hi Gents,
Thanks again for the responses.
I have checked the Fuse No. 1 and found it to be ok.
I carried out a basic check of the supply voltage to the DCCV solenoid plug at cold prior to starting the car and with an external Temperature of 22C (72F) and the main control panel set to LO manual and recorded following supply voltages on the DCCV valve plug as follows:-
Left side of plug (Passenger side of a RHD vehicle) at 1.4VDC
Right side of plug (Driver side of RHD vehicle) at 11.98VDC (no engine running)
New DCCV unit I have installed is a Bosch valve as was the old unit I removed, which on checking by applying a 12vdc supply to each solenoid appears to be fine and all ports are clean and clear. Perhaps i didn't need to replace this after all.
With these reading and given what I understand reading through Karls Fault finding, at dead cold and LO setting and 22C external temperature, I would expect a 12v supply to both of the DCCV solenoids to stop any heated water flow.
My next step is to look at the Duct temperature sensors and perhaps the main sensor under the ignition key, which I have already inspected and cleaned. I will start taking some resistance readings of these devices based on Karls figures.
I'm working through it.
Regards Jeff

 

Hi Gents,
As an aside from my problem previously written, can anyone tell me the difference between a 5 port (hose) DCCV valve and a 3 port (hose) valve. It seems to me that the 3 port is much easier to replace.
Can a 5 port be replaced for a 3 port for future reference? I appreciate that there may possibly need to be some hose redirection to eliminate the extra 2 hoses on the 5 port, but it seems to me that this has already been done via the 3 port valve. Perhaps I'm mistaken and it won't be the first time.
Regards, Jeff

 

The 3 port ones fail more often so I'd avoid them!

 

No they don't interchange. Replace it with the one that was in there.
3 port is for 2003-2008 and the 5 port is for 1999-2002.

Here is another good HVAC web site.
Jaguar Climate Control
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Jeff,

Careful with your method of troubleshooting. You may be steering yourself down the wrong path.

For most circuits, including the DCCV, Jaguar uses a switched ground system. Most vehicles use a switched supply system, with a fixed ground. Jaguar did just the opposite, with a fixed power supply to a component, with the control module supplying a switched ground to complete the circuit. With the DCCV, it's not just a simple on/off, either. It's Pulsed Width Modulation (PWM), a fancy word for switching the circuit on/off rapidly in a controlled fashion to control the current flow.

Although you took some voltage measurements at the two outer contacts at the DCCV connector, what you really need is a resistance reading to ground instead. You'll also want a voltage reading to the center contact, i.e. the fixed power supply (battery voltage).

A voltage reading (instead of a resistance reading) on a PWM variable ground circuit can be very misleading, and does not tell us much. However, even though not especially useful, I would expect both side to be the same when in manual LO. This leads me to suspect either a bad control module or a wiring problem. The early models are not prone to burnt traces like the 2003+ models, although it can't be ruled out. Personally, give the chance to spend your time and money, I'd first check continuity from those two outer contacts to their respective contacts at the back of the control module.

Wiring diagrams here, at the top of the page:

JagRepair.com - Jaguar Repair Information Resource

Once you've opened the PDF, scroll to Figure 06.1. The DCCV is near the bottom left of the page.


Also, now that you've removed that jumper from the DCCV connector, what symptoms are you seeing? Are you getting full heat at all times from one side?

 

Yes.

The 3 port valve has 3 ports.

The 5 port valve has (wait for it...) 5 valves.

AFAIK, there's no reasonable method to swap one type for the other. If you should discover your existing DCCV has failed, please see this thread for an in situ repair:

https://www.jaguarforums.com/forum/s...repair-251854/

The main housing should theoretically last forever. Only the internals need to be replaced. With the method above, you don't have to touch the hoses.

If still inclined to replace the entire DCCV, rather than mess with the hose connections in such cramped quarters, disconnect the hoses at the other end where access is better. Pull the whole octopus-looking assembly with hoses attached, and then you can access the tight connections at the DCCV from the comfort of your workbench.

 

Hi Karl,
Thanks for your informed reply to my queries. Yes, I am very ofay with PWM, as I mentioned in my initial post, I am an Engineer of the Electrical Type and at the tender age of 72, have certainly had my share of experience with various kinds of PWM control systems, especially as I have spent most of my working life in process control largely in the heavily automated food Processing industry. Long and short is I understand its function and operation. I'm not convinced that the application it is used for in the Jaguar CCM/DCCV system is necessarily the best, as it would certainly limit the life of a solenoid valve, compounded by the environment it is operating in (heat, cold, vibration etc) with most solenoids under a PWM having a recognised life of between 1 to 3 odd years. This is probably the reason why DCCV valves are so prone to problems and a relatively short life. There is also the problems of back EMFs - spikes resulting from both inrush and release currents from the solenoid coils, which would require some form of either bleed dioding or clamping circuitry built into the CCM Module. This is also probably what causes the burn out issues in the later model CCMs.
Proportioning/modulating valves would probably have been far more effective and longer lasting for the application, but I guess it was all due to both space and a dollar cost and to coin an old phase by Mr H Ford - "We will make money on spare parts"), but hey I digress.

I have checked the continuity of the respective cables back to the CCM unit and found them to be in tact. Irrespective of what I do in adjusting temperature from LO to HI, full cooling etc. and the various methods described in your extensive and very thorough troubleshooting guide, the voltage reading to one side of the solenoid block does not change and remains constant at 1.4VDC to the drivers side of the vehicle (RHD - I gave you a bum steer earlier when I said the passenger side , I miss read the plugged on position) and 12VDC on the passenger side solenoid and yes, warm air is coming out of the vents on the drivers (right) side with tepid air on the left. There is 12v power constantly on to one side of the solenoid block plug, even when the ignition is switch off and 1.4v to the other. I would expect power at 12v to be on both solenoids (flow shut off when powered) until such time as call for heating is made deliberately via the CCM Module and associated control buttons.
If I now revert back to my original post and the jumper wire in the plug, I believe this as you suggest was a Hokey fix, that someone attempted as a cheap (this car's history has a story for another time!) fix for a problem with the main CCM module which obviously didn't work very well and I have decided, that I would be best in light of the various current investigations I have carried out, to now simply replace this as I have already replaced the DCCV unit and that did not fix the problem. I also note, that replacing the CCM module may not necessarily rectify the problem, but I'm prepared to make that gamble. In hindsight, the old DCCV is probably OK and certainly tests out that way.

I also note your suggested post of the CCM repairs, but on closer reading, they do not repair early Jaguar CCM units, only after 02 models. I will look for one on the web.
Thank you again
Regards Jeff
PS. I note you appear to be from Oregon and I have some very fond memories of my brief time in Portland back in the late 70s - especially at a night club in Beavertown (EE)

 

It's okay. We don't judge.



Hmm, I wonder if maybe you've got two wires rubbing together. Each wire will still indicate good continuity end-to-end, but such a test does not check for continuity with an adjacent wire. It's a slow process, but it may be worthwhile to check the suspect wires for continuity with everything else in the same bundle.



You're new here so will be excused this time. When sucking up to me, it's customary to also include something alluding to my magnificent physical appearance and pleasant manly scent.






Temperature values, please. Ambient and both ducts, AC on and off. You may have more than one active fault. In the troubleshooting guide, please see post #2 for more details of how to test the DCCV.



This part has me very confused. Of the three wires at the DCCV plug, the center should have hot battery power at all times, ignition on or off. This is the common power supply to both coils in the DCCV. When the ignition is off, I would expect nothing at the two outer contacts, the PWM variable grounds supplied by the control module.

There's some possibility trying to take a voltage reading where a ground is expected (at the two outer contacts) may give inconclusive results. Regardless of what you should see, I'd expect both outer contacts to be the same when the ignition is off. As power is always present at the center contact, the ground would have to be removed from the outer contacts. Otherwise, the two coils would remain energized when the key is turned off.

This leads me back to my previous thoughts on wires rubbing together. Or maybe some additional hokey wiring mods were done, attempting to "fix" the problem.





Have you considered opening up the module and giving it a good visual inspection? Look for burnt traces on the circuit board, blackened resistors, and swollen capacitors. If the damage is not too extensive, you may be able to repair it yourself.



eBay is typically an excellent source.



I have been here since 1990. Sadly, this once beautiful city has become like something out of a zombie apocalypse the last 5 years or so.