No disagreement with that, and it looks odd from the get-go. It's tight in there so I guess the thinking was that shaping it that way would reduce the risk of a kink - either that or the non-return valve was an afterthought.

Having the pump so difficult to access doesn't help troubleshooting either.

 

The problem is now solved .
I unplugged the water valve and turned the heater to HI and got fried ....the only control is the fan speed.
However, that sensor near your knee also controls the air con temp and I always thought the air con was very powerful....well it would be . The fan drawing air over the thermistor had failed so just like the heater was full blast 24/7 so was the air con. I removed the original fan and epoxied a 40mm computer fan onto the dismantled housing to draw air over the thermistor and all is well.
I noticed in traffic if I had the air con on that with extreme cueing for the Dartford tunnel on a hot day the engine would go up to 100 deg C . I think the AC radiator just in front of the main rad was preheating the cooling air .
So now the AC clutch should go on and off and the water valve open and close as it should in response to the thermistor temperature.

 

Does the little vent by your knee (thermistor cover) just pry off with a screwdriver? Easy to get off?

 

It does pry off fairly easily, however when i went to push mine back in, it pushes the housing back, so it doesnt sit flush with the knee pad, so im going to have to pull the knee pad to get it to push in completely. On the plus side, i guess ill check to make sure my fan is running too. Just something that might happen to you too lol

 

No the thermistor and fan are accessed from behind the panel...pull the panel horizontally at the top edge and it clicks out the fastenings ...two screws at the bottom only need to be loosened not removed.
Unplug the sensor and the valet switch and take the whole knee panel out .

PS the thermistor was 1.7 k ohms at 20 deg C so if yours is open circuit you need what they call a 5k thermistor ( they come in 1,5 and 10K sizes)

 

You really have to remove the whole knee bolster. There are 2 (10mm?) screws at the bottom, and 2 tabs near the top. You might have to move the steering column up/down to clear the control knobs. There are a couple of wire harnesses involved, so you have to be a little careful. It's a 5 min job, nothing to it. You should then see the aspirator and the sensor.

Best of luck, keep us posted.

 

I pulled the panel yesterday. The thermistor was dirty, but not that bad. Cleaned thermistor, hose and fan unit with compressed air. Re-installed and still no heat to speak of. Will wait until the weather actually gets colder before pulling the plug on water valve.

 

Did the fan run with the ignition ON ?
If it did test the pump ( ohm meter on the terminals)

 

I unplugged the water valve connector and still no heat this morning. I need to do the diagnostics check again because with the heat on, the windshield kept fogging up. Then I had to turn defroster on and that is pure air conditioning.

 

pump not working

 

I turned on the climate control system and turned key on but engine not running. I could hear a whirring noise down in that area. I assumed it was the pump running??

 

I assumed it was the pump

Test don't guess to quote Suntester ...I have to use a mechanics stethoscope on mine to tell if its running. If you pulled the white connector and no heat then its the pump or the heater is blocked
You need to test the continuity of the motor with an ohm meter at the black connector terminals ..wire end or via the fuse box .
What about the fan on the temp sensor? Did you see if that was running?

 

I had a related problem years ago where I would get heat even when I requested cool air. The problem was that the water valve would stick open, thereby allowing hot coolant into the air box and overcoming the cooling effect of the air conditioning system. The water valve is spring loaded open so it's normally open. It is electrically closed when you select air conditioning.
The solution was to give the valve a love tap with the air conditioning on and after doing that a few times the problem hasn't resurfaced for years.
I carried a mallet and pipe in the trunk for a while but no more.

 

Update. Items checked to date and still no heat. I am now questioning if one or more blend door actuators are not working. Does not seem easy to reach to check these out. Looked at all the videos and still not perfectly clear. Apparently have to lay upside down in footwell under steering column to see. I removed the glove box and verified the Recirculating actuator operates properly. No other actuators on passenger side.

1. Drained, flushed and refilled coolant system. Replaced new water pump and thermostat.
2. Pulled the white connector to water valve and still no heat.
3. Tested the continuity of the pump motor with an ohm meter at the black connector terminals at wire end and via the fuse box . All tested fine. Pump was running as we removed the relay. It stopped at that time, relay replaced.
4. Checked all fuses and relays with ohm meter. All are good.
5. Pulled thermister and cleaned. Fan was running on temp sensor
6. All fans are blowing strong, just no heat at all.

 

Student Guide Publication T703/02 Jaguar Climate Control Study Guide.
This should get you info you need.

 

Earlier Version of CLIMATE CONTROL student guide Publication T 701/98

 

XK8WMG...
Be aware
With the water valve unplugged and the heat setting on HI you should get loads of heat . If no heat then the valve could be stuck ( tap it with a pipe and hammer its rubber mounted ), remember the pump has a magnetic drive to the impeller so it could be going but not driving the impeller due to debris/bearing failure etc.
The heater core could be blocked. Check temps with fingers on the two pipes feeding the heater core.

 

I have found that debugging the water valve and aux pump can be a challenge. If there is no flow, it is hard to figure out which one is blocking, if any. There is no easy access to any of the parts involved either to try shunting hoses or anything creative. Next cheap/easy step is probably to do a cleanup of the heater core.

You can see the tubes to the core going through the firewall. It is fairly high up, by the brake booster. You will need long needle nose pliers to reach the hose clamps. Long hose pliers are super useful for this job, too. For the flush, I used clear tube (5/8?) in a pack and a barb to garden hose adapter from the hardware store. You will need to flush forward and back by swapping the tubes. This is done with simple water pressure from a garden hose. Think of keeping the liquid being flushed in a bucket for inspection. While there, use radiator cleaner through the supply hose. From memory, it needs to stay in the core for about 10 min. Then flush again. Be careful putting the hose with the one-way valve back on. Make sure that flat section goes on in a way to allows proper flow.

In my case, the difference was pretty dramatic. Starting from basically no heat before the cleaning, I had some some heat in the cabin with the engine running maybe 30 sec.

Another test you can do is remove the center wood veneer face, and then unscrew the vent assembly. If you set the heating to Face, the door should open and give you an (indirect) look to the core (use a mirror). Maybe an infrared thermometer can measure the core temp as another data point.

Best of luck, keep us posted.

 

Ok so as an update to my post earlier about just prying off the cover on the knee sensor, SCRATCH THAT! LOL! I took the time this morning and pulled the bolster and looked at my stuff. My tube was partially clogged, and my fan, which does work thankfully, was partially clogged too! I blew them out with compressed air and put it all together again. YES, as others wisely said, taking the bolster off is the absolute BEST WAY to clean and check your fan and tube. 🙂🙂

 

I fitted a bosch 0392020039 pump . This fits at the top and replaces the squashed hoze ..pump down body up . I have written it up somewhere ...pump is 19mm inlet/outlet which is OK for the horisontal connection to the heater matrix but you need to adapt to 16mm for the downward facing bit . Put a diode on the brushes to arc suppress. Got mine from amazon but the price seems to have jumped up.
Beware of some pumps as when you get them you find they are brushless and need a pulsed /variable speed supply this is a simple brushed motor . no impeller clutch.
Just found this one ..same pump but half the price for ford