Good evening,


New to the forum but have long lurked... I live in Annapolis, MD and bought a '96 2+2 several months ago with 52K miles. I've managed to sort out a few issues and am thoroughly enjoying the car with the help of the expertise of this forum.
I've read every thread on overheating but I'm still a bit confused. I'm embarrassed to say I can't find the radiator temp sensor. Manual says it's in the water pump inlet. I sure don't see it. I do see a sensor located on the radiator right in front of the air filter housing with white/blue wires. One poster asked if this was the radiator temp sensor but I didn't see that he got an answer. The wire color does not match the wiring diagram (that was also in his question). If anyone can shed some light and give me specific affirmation that the sensor I see on the radiator is indeed the temp sensor that controls the auxiliary fan or where exactly I need to be looking around the waterpump, I sure would appreciate it.


Many thanks, Mitch

 

Hi Mitch

I'm presuming that your XJS is the 6cyl version? Fig:17

If so check this out: https://www.google.co.uk/search?q=1996+xjs+engine+diagram&client=firefox-a&hs=ijc&rls=org.mozilla:en-USfficial&channel=sb&source=lnms&tbm=isch&sa=X&e i=-rBuU-ioPIGyPIyQgNgP&ved=0CAgQ_AUoAQ&biw=1920&bih=941#fa crc=_&imgdii=_&imgrc=WRcdOiNHHqp4wM%253A%3BvOCfHg4 wAaItbM%3Bhttp%253A%252F%252Fwww.jaguarforums.com% 252Fforum%252Fattachments%252Fxjs-32%252F56210d1380248896-cruise-control-1996-4-0-2-2-aj16-jpg%3Bhttp%253A%252F%252Fwww.jaguarforums.com%252F forum%252Fxjs-32%252Fcruise-control-1996-4-0-2-2-a-103447%252F%3B659%3B700

 

Good evening,


Thanks for the info. Yes it is a 4.0; only engine offered in '96. Had troubles opening your link but finally got a picture of the engine with various components identified with pointers. I thought the radiator thermal switch and the coolant temp sensor on the thermostat housing were two different things. I now see the coolant temp sensor tied into the HVAC system is located in the passenger compartment. Also thought the inlet to the water pump was on the bottom; should have realized that it was at the top.


Really like your '95 Beautiful car!


Again, appreciate the help.

Mitch

 

Hi Mitch

I also had trouble opening that link when I posted it, so I must have put it up wrong but glad you managed to hopefully find what you were looking for.

As for my '95 Beautiful car!

Just hope and pray you never have to fit a New Fuel Pump!

On mine it sits in the top of the tank and I had to remove the fuel tank in order to replace it!

I'd rather do an engine swop than go through that again!

 

Hi Mitch,
Great to hear you were able to get a 1996. I suspect you are correct about the sensor on the radiator controlling the fan but I will do some research and see what I can find out for sure. The sensor at the water pump area I believe is what tells the computer the temp of the engine. Again, I will do some research with the books I have and let you know what I find out. I would check with the companies that supply parts for the XJS as I am sure they will be able to tell you what that sensor does and how much it is etc. They usually have pretty detailed parts pages showing the locations and names etc. of each of these parts so sure they can quickly identify this sensor but I will check what I have and see what I can tell.

Again welcome and look forward to having you on board.

 

Fesiwig,

On the AJ16, there are 3 water temperature sensors. On the thermostat housing there is a sensor which drives the temp gauge. There is also another sensor (technically a thermistor, I think?) which provides a signal to the engine ecu. Then there is a thermostat switch mounted in the rad which controls the auxiliary electric fan. I think that the sensor that you refer to in the passenger compartment is just the cabin aspirator motor sensor of the A/C system.

I'd really suggest that you buy Jaguar's Parts & Service manual on DVD. Really cheap via Jaguar Heriatge. It may just me, but I wouldn't consider running any of my cars without a decent Service manual.

In the meantime, the best way to identify the parts is to look at Jaguar's own online parts system. Better than going to a supplier catalogue IMO.

See here for the 2 sensors on the thermostat housing:

Thermostat and Bypass Hose-4.0 Litre - Parts For XJS from (V)179737 to (V)226645 | Jaguar Classic Parts UK

The radiator thermoswitch is here:

Radiator-4.0 Litre - Parts For XJS from (V)179737 to (V)226645 | Jaguar Classic Parts UK

and the cabin A/C sensor is here:

Air Conditioning Aspirator - Parts For XJS from (V)179737 to (V)226645 | Jaguar Classic Parts UK


Hope that all helps

Paul

 

If you think your Aj16 car is overheating, the best thing to do is to go get a OBD2 reader and get the temperature directly from the CTS. Also use a infrared thermostat.

What is the exact problem you are having?

 

Appreciate the replies. I do have a manual but, unfortunately, it's misleading at times. It clearly states the radiator thermal switch is on the water pump inlet. It also states that the coolant temperature sensor feeding the HVAC controls is located in the passenger compartment, left side, under dash on left hot water pipe. I suspect that's wrong and the HVAC related sensor does sit next to the engine temp sensor on the thermostat housing. Further, the wiring diagram shows the auxiliary electric fan control circuit to be fed from the same fuse as the fan itself when in my car the control circuit to the relay is switched with the ignition. So, my manual is not providing me the detail I need. Not sure I really have a problem but I've never heard the auxiliary fan operate and with the advent of warmer weather, I want to make sure the system is working properly. Yesterday, with the AC on full, the temperature gage ran up past the N which I had not seen before. I've checked out the relay and jumped the right terminals to get the fan running. I've also checked the 12 volt source for the relay control circuit. The only thing I haven't been able to check is the sensor. The sensor on the radiator in front of the air filter housing doesn't correlate with any wiring diagram I have so I'm reluctant to mess with it until I'm confident that it's the right one. The wires to it are white with blue rings whereas the wiring diagram I have shows the ground leg to be black and the switched leg to be green/brown. The white/blue wires also look like a very thin gage which also makes me wonder. However if it's not the radiator fan sensor, wouldn't know what it would be. Would like confirmation from someone with a '96 that the sensor in front of the air filter housing is really the radiator thermal switch.
Again, thanks for the help.


Mitch

 

Mitch,

I'm not sure which manual you are using but the proper Jaguar manual is very clear about the desription and placement of the thermostatic switch in the top left of the rad. It even has a section (26.25.35) which describes the replacement of the switch.

The white and white/blue is a bit misleading. There's a wiring junction plug just a few inches away and the colours then change to the described black and green/brown.

So, yes, you are looking at thermostatic switch. Expensive but still available from Jaguar today. See here if you need to buy a new one:

Radiator-4.0 Litre - Parts For XJS from (V)179737 to (V)226645 | Jaguar Classic Parts UK

Hope that helps

Paul

 

Outstanding! Many thanks!


Mitch

 

I was glad that I found this thread as I had misinformation about the location. I also was able to find the directions from the service manual section noted. My dealer told me that part is discontinued, but I bought an FAE part online (Spain manuf.). I'm not certain why manual tells you to remove lower radiator hose, as the sensor is so high up, I don't know why one would need to drain entire cooling system. My fan comes on with AC, but doesn't come on when temp gauge reads 3/4. I have been putting inside fan on heat, which is very unpleasant on those hot summer days in traffic!