Cabin Heater

[J44EAG]

Vernon,

Can you tell us exactly or approximately where on that front loom where we should be looking please?

Mike

[rosemary]

Hello Vernon
Thanks for the tip,like Mike a pointer might help. I am about to remove the glove box and have a look at the RCCM ref
Doug's picture to see if I can ID anything before buying one from the scrappers.

[rosemary]

Hello All
I've removed the RCCM and opened it up,low and behold it's fried. I can see, in exactly the same place as the photo in the previous post by Doug, the burned track. I have taken a photo but can't figure out how to upload it here. Spoke with Lancaster Jaguar Amersham, the cost of a new one is circa £600 inc Vat roughly a third of the value of the car.
Ebay here I come and fingers crossed.

[J44EAG]

Dave,

Pay no more than one third of the new price if you buy second hand. Make a note of the exact part number and replace with a like part.

Eurojag may have one if you give them a call.

Also worth contacting BBA Reman in Rochester. They recondition various electronic components.

To upload an image, go down to the submit button and just below that you will see "upload attachment". Just below to the left you will see the grey box with "Browse" in it. Left click on that and your computer library page should come up. Click photographs, select from the appropriate file, click on your selected image, right click to give options then left click on "select". Then click "Add the file" when you see the JPG number alongside the "Browse" box. A pop up box will appear as the image is loads to this site. Go back to the text and place your vertical curser where you want the image to appear in the text. Below the white text writing area on the bottom left you will see the JPG number of the image. Just to the right, click on "Place in line". Click on that and you will see an alpha numeric code appear. That is the picture loaded to your post. Job done.

When you submit your post you will then immediately be able to review what you have just posted. Within that text should appear your image. You can always edit your post if for instance you have loaded the wrong image by deleting the alpha numeric code. That will remove the image and you can replace it with another image if you wish by going through the image loading sequence again. A couple of practices and you should be ok. Its little different to adding an image to an email.

Mike

[Martec]

Just a quick one, to stop the next Climate control ECU going the same way as your present on you could fit a 1 amp fuse way into each return from the heater valve. Pull the plug out of the heater valve, check which of the 3 wires is carrying the 12 volt live feed, then cut the other two and fit the fuseways into them. I did this and used extra wire to lift them into an accessible position.

Several items including the heater valve are supplied by a 10 amp fuse, the heater coils can fuse over and allow full ampage to the CC ECU.

Brian

[oldtimer]

Hi Brian,
Would you kindly amplify the last sentence of above thanks.

Today, I do not have a problem but who knows tomorrow. So when the weather warms up may be worth introducing a couple of inline fuses to reduce the risk.

Seems like the eyes have it !!

P

[rosemary]

Hello All

I've been on to JoJags Ltd and they are sending me one(numbers matching) guaranteed in working order for £120.
Before ordering Mark at jojags said whatever I do change the heater valve before fitting he said they have dozens of these, all repaired, from cars where the heater valve had failed, he said it happens every time. He also recommends fusing the two solenoid returns to protect the RCCM

[Martec]

The 10 amp fuse supplies power to:

The heater valve
The V8 Auxiliary cooling pump relay
Air con Comp Clutch relay

The power to the heater valve can be 10 amps max (obviously) and the windings of the heater valve solenoids reduce the ampage to the climate control unit to 1 amp max. Due to water leakage into the solenoid or the old insulation breaking down the current can flash over the windings reducing the resistance to zero and so maximum amps, AA ECU fried and fuse blown..........I would think!

The above is for the early cars and probably the same for later car, the earlier CC ECU is less prone to this fault so we are told but I didn't fancy the cost of a new/ recon unit as per Rosemary and Mike so cut the loom and fitted fuses (1.1 amp) as below. Now I need to reat my eyes.

[vernon]

I hope it's not to costly to replace.

Mike the problem area of the front loom, seems to be under the near side headlamp.
There is a spur going of at that point and the loom is quite tight, my loom was also wet inside, water ingress from the spur junction.
Always worth a look if you have wiring problems.

Vernon.

[J44EAG]

Yes, I have heard of that issue on an STR where that run of spur cable runs though the front panel work under the air cleaner box and chaffs through insulation down to the bare cables. Then pop! Dead shorts. I believe there is a similar tight spot near the O/S headlight and problems also within the loom behind the N/S wheel arch shield.

The case of the STR was that it locked the transmission in Park. The car had to be transported on a Transit type slope bed recovery truck but to make things worse the car was parked in a narrow street with cars either side. Eventually the car was dragged with rear wheels locked, down the street by the truck before enough space could be found to load effectively. Again it was dragged onto the transporter bed with wheels locked by the winch on the truck. Not good for tyres or transmission!

Mike

[oldtimer]

Hi Martec,
Thanks for the above photo, that is really useful

P

[jeff1954]

Mike is that diagnostic tool easy to use/understand as electronic gizmo's, are not my forte.

Jeff

[J44EAG]

Very easy to use. Plug in to the OBD port in the car below and to the left of the steering wheel. It is powered up by the car electrics. There is a simple set up and you then select your car and year. Various options present themselves and you go to the area which you wish to test. You run the scan on that section or set to auto when the unit looks at most sections of the car, but the unit tells you what sensor or fault is present and you then use that to start your hunt for the unit or plugs and sockets that might be the cause of your issue.

I note in the listing that the price has now fallen to £90. a most useful piece of equipment in my opinion and rather easier to use than some of the CD discs available for use on a PC.

Google, Youtube iCarsofti930 and the sales guy from UK Diagnostics will show you how it works. If you can work a mobile phone, you will be able to work this unit.

Mike

[Martec]

Thats me stuffed then!

Brian

[rosemary]

Hello All
I wonder if JLR read these posts and "learn" if not they should, I would like to know however if access to the plug on the heater valve is possible from the top rather than from below, I can't see anything from above.