Feel for the water routing solenoids and heater pump relay to click as you turn it on

Heater pump # 3 / 10 amp engine compartment fuse box ( relay control )

Swap relay # 1 Heater pump engine compartment fuse box , there is a # 15 / 10 amp fuse in the box

Solenoid has no relay or fuse .

 

I am going to jump in on this faulty heater thread. I have had problems with heat in my 2002 XJ8 since I bought it a few years ago. I recently replaced the aux. pump. BTW, I bench tested (using the car's wiring to the pump) the new one AND the old one and they both worked fine. They pump A LOT of water BTW.

So I have a couple of questions. Were is this inside sensor that was mentioned earlier. There was the mention of moving a kick panel. Which panel?

And is there a mechanical or electronic valve near or at a heater core that will stick or break?

Thanks for any suggestions.

 

On a LHD you should see some vent slots below the steering column to the left . There is also a ambient temp sensor below the left headlight inside the brake cooling duct . you can best see it as you look down the duct from the outside front with a flashlight .

The X300 climate control system has a control head self test that puts out fault codes covering these 2 temp sensors , I would think the X308 has the same feature .

See link below :

https://www.jaguarforums.com/forum/x...nfo-faq-66454/

 

Where is the heater control valve (Item 1 in the diagram below) located on an XJ8? Are these know to stick in a closed (or partially closed) position? When there is power to this valve it is open (water flowing) or closed?

It looks like you can get a new one for a S-Type for 50 bucks but one for the XJs are $ 550! Has anyone had a good response "re-conditioning" theirs?

 

I was about to mention the valve yesterday already.
It is located in the engine bay, against the firewall, under the middle cover.

I have read they do break down (get stuck) from time to time, mainly caused by a reaction of the seals to (wrong?) coolant.

The valve is modulated (so not "on-off"), and gets 12V in pulses.
If the temperature is set on HIGH, the valve should read ~6.5V if memory serves well.

If you lower the temperature setting, The valve will get shorter or longer pulses of the 12V, and closes accordingly partially or completely, depending the dash setting.

 

In a pinch you " may " be able to remove the motor and fix the valve open using the blower fan speed to control cabin temp . Some valves have a lever on the side and could move the valve and fix with the connector removed .

 

h iall thanks for the info on heater motor.now this is were i am with it.i have fitted a secondhand motor which works well.but after fitting still did not work off the vehicles electrics.so i found that fuse 3 in the engine fuse box was blowen.i also found a link on here telling me what was the cause of the blowen fuse .which turned out to be the alarm sounder.so after disconnecting the plug to sounder bingo the fuse was cured.but still no heater pump working.so next i pulled the relay and put a jump wire on 2 of the connections and then i could hear the pump running.so now i have tried a relay from one of the other relays fitted in the same fuse box and still nothing.now surley not every relay is duff so has any one have any idea of what it could be thanks

 

Yes , relays come in many different ratings , swap with one with the same part # as the ones in the truck has midrange relays

 

hi lady penelope .as you know there are a few relays in this fuse box in the shape of a t.well would not all of these be the same as i have tried every one in its place and did not activate power to the pump.,but if i put a jump wire across 2 of the relay terminals bingo all works.,maybe do you think it has to be the correct one.also y on this thread would you know if the heated seats and front and rear window heaters only work when motor is running as they have mystery stopped working.thanks
m

 

I'll get to the window and seat heat on the thread you opened on those issues as your priority is the cabin heat with front window defrost

See Highhorse's reply on that thread and I agree . Jaguar's like full tummies as a full battery charge of 12.77 volt and as it gets lower the ECU's act up one being the Climate Control ECU which provides a ground to pull the power contact on the heater pump relay . As the heater pump brushes arced the relay power contact probably arced as well and was damaged .

 

hi would just like to thank everyone who helped me with solving my heating problem.all sorted now i think this site and people on it are brillll really has helped me big time thankyou all

 

Just out of interest, did you find out why the relay(s) were not powering the circuit?

 

As an aside, as I had jumped in on this thread earlier: after confirming my heater pump was working and still NOT getting adequate heat, I banged on the top of the heater valve firmly and I think this opened the (probably stuck shut) valve.

I am now getting much better heat but ONLY after the car has really warmed up.

BTW, I have owned (and please don't get mad for me saying this) BMWs and Mercedes in the past that the heater pumps WILL work when the car is not running but with the key is the ON position. This is great because it allows for the circulation of hot water from the engine block thru the heater coil and will continue to give you heat without having to run the car.

 

hi rob yes.that water heater pump.will not operate untill the car is started and when the engine starts to get warm i noticed with my mulitimeter touching the pin connections which come from harness to pump i started to get voltage as the engine warmed up which then i connected and bingo heater pump-running and nice hot heaters now.the relays i think only get power to them when the car warms up.also my heated seats and front and rear heated screens only work when car is running .thanks for your help