Hello everyone,
I have the COOLANT LEVEL LOW warning.
I replaced the sensor, but the warning is still there.
Does it take time to reset or should it register the new sensor right away?
If it doesn’t go away, I guess the next step is to replace the reservoir.
Any suggestions?

 

Can you check the resistance across the sensor terminals when the tank is empty and full by syphoning out the coolant temporarily? You can probably find what the value should be online. Compare these values with the values for the original sensor. I would have expected that the new sensor would work immediately.

Richard

 

The problem is often due to the float inside the tank being stuck. As I recall, it's a ring with a magnet.

 

Sometimes it's better to just replace the expansion tank, which comes with the sensor, and be done with that.

Usually, by the age the sensor has failed, if it failed first, not long after, the tank will start leaking at the seams. And if it isn't leaking, it's likely the float is stuck, which I bet is your situation.

 

No. That’s beyond my ability and it would be easier to just replace the tank.

 

For what reason , I don’t know, but I had to replace the whole tank once when just replacing the sender didn’t do anything.

my magnet donut looked OK, but I have
read on this forum that build up of debris on the magnet can impact the circuit, IDK.

Z

 

PS: You can attach ohm meter leads to the sender (while it’s in place) and move the magnet up and down with a wire bent with a hooked end. The meter should show a different reading when the magnet is moved to the top then dropped down.

this is easier done on the workbench than when having the tank installed.

Z

 

When replacing the tank, do you just suction out the coolant, then remove and replace the tank and refill it?

 

Essentially yes. Some use a turkey baster. I use a cheap Harbor Freight hand suction pump kit. Suck out as much coolant as you can, then place old towels all around the base of the reservoir to soak up as much of the coolant that will spill (or just dribble if you are lucky) when you loosen the clamps, pull the hoses, and remove the reservoir. I replaced what I presume to be the factory reservoir in my wife's 2006 XK8 six or seven years ago. They all eventually begin to leak at the nozzles or at the seams, so I have a brand-new replacement reservoir sitting on my garage shelf awaiting installation when the time comes....

 

After you refill the new reservoir, you will probably need to burp and add more coolant to the system for the next several days before the coolant level finally reaches and stays at its normal point (which is just below the reservoir's filler neck)....

 

One other tip, the large hose on the bottom can be plugged with a wine cork to avoid additional coolant spills.

Save the wine for celebrating after a job well done.

 

yes.

 

I will add as a reminder just cos no-one has even though it should go without saying - do not drain/remove/replace the expansion tank unless the car is completely cold.

 

Well that would have saved me a lot of pain and suffering,🤡

 

I’m changing out the reservoir. I was trying to remove the upper hose, the one in the corner, next to the blanked out hose attachment. The hose is rubber, then plastic tubing, then rubber. The plastic is brittle and it cracked. Any quick replacements out there or do I have to buy the Jaguar part?

UPDATE: I ordered the factory hose. To get me by until the factory hose arrives, can I just run a rubber hose, similar to the two ends of the factory hose, all the way from the reservoir to the thermostat housing?

 

Yes, you can use a rubber hose. Fuel line hose works.

 

REPAIR COMPLETE.
I replaced the reservoir. It took longer than I expected.
I used a fuel hose to replace the cracked plastic tube. The warning light is gone. No leaks. I appreciate all of the help that I always get from this forum.
Merry Christmas to all of you!

 

I used a rubber hose for a permanent solution. Makes no sense to me to have rubber/plastic/rubber. My coolant tank was brittle and broke the nipple off the tank. Still looking for a metal thermostat housing, mine also broke off a nipple on that. It always something!! TM

 

What were Jaguar thinking when they designed that hose? It’s rubber fuel line, then plastic, then more rubber fuel line. There has to be a reason.

 

I did the same thing years ago and never looked back. Sure it doesn't look OE but it more than gets the job done. My only complaint is that on the XKR, there are two such hoses. One is routed towards the radiator, whereas the other snakes its way between the supercharger and charge coolers and connects at the water outlet, next to the coolant temperature sensor. Naturally it gets cooked between these two structures and I have already replaced it twice while doing other maintenance.