My chariot, 2003 XJR, now has 237,628 fun filled supercharged miles under her chassis.

There are two cooling fans behind the radiator that are staggered at 45 degrees.
The BOTTOM FAN comes on when the AC is on and I'm stopped.
The TOP FAN has never kicked on, ever.

The gauge doesn't show the motor is running hot.
But overall it's way to hot under the hood.

Shouldn't they both come on together?
Wouldn't they both be on the same relay?

When my beast cools I'm going to do a continuity test on the TOP FAN motor.

Has anybody else experienced this? Any other thoughts?

Thx guys. Love this place!

 

Both fans should run together, and they have Low and High speed modes. In the Low speed mode, the fans are connected in series and in the High speed mode in parallel. This is achieved by a special triple relay, located somewhere lower down inside the front LHS corner. As you mentioned, start with checking the non-functional fan and checking the fan fuses. Checking the continuity of the fan may not give you reliable results. It is better to disconnect its loom and apply 12V directly to it.

 

On the X308 V8 the both fans running is triggered by the coolant temp sensor that feeds the ECU what to do with the information

The ECU tells the fan control module ( a multi relay package in one located under the car just fwd of the front left tire ) to have one or both fans running

in troubleshooting the right fan connector can be moved over to the left fan

In the AC mode there is a low and high pressure switch ( called the refrigerant 4 way pressure switch ) which determains you have a high cabin cooling demand so it triggers both radiator fans to come on

You can without the engine running but the key to on jumper the high pressure switch to trigger both fans

This will test the fan control module as well as both fans in the original wire placement configuration ( not swapped fan connectors )

See page 61

http://www.jagrepair.com/images/AutoRepairPhotos/jagxj2003.pdf

and for the 2003.5 model year page 38 ?

http://www.jagrepair.com/images/Auto...agxj2003.5.pdf

 

The AC will switch the Low fan speed up to certain pressure; above that it will switch the High fan speed on.

 

Ok guys it maybe this simple??

Took the non operational fan out.
Did a continuity test - Nothing.
Put some 12v DC love to it - Nothing.

No continuity, no action with direct 12v love.....
Just a blown fan motor?

 

Sounds like a bad motor. Can you take it apart and look at the brushes/motor to look for broken wires, missing brushes or loose solder joints?

 

I agree. Check to be sure the bad motor did not blow the high speed fan fuse. It is fuse number 14, a 30 amp fuse in the bigger fuse box under the hood, left side.

 

Gentleman I'm back in business.

as a youthful man of 58 years young I've always use the expression you can't break something that is broken.

I was able to take the motor apart and I found it was completely full of graphite from the brushes.

cleaned out all the graphite and then cleaned everything I could see with electric contact cleaner back to shiny new.

Tested the continuity and it was strong as new. Put the fan motor back together gave it a little 12 volt love and boom, she jumped back to life.

for what it's worth, if you can get something apart, do it take a look and who knows it may end up being this simple.

 

Great work! But please check fuse #14. The fans run in series at low speed, using one fuse, but they switch to a parallel circuit on high speed, using two separate fuses. They will both run until they switch to high speed, but if fuse #14 is blown, one fan will shut off. Just a precaution since you know the fan was bad. It sure could have blown that fuse.

 

Checked fuse per your encouragement.

Oddly enough, fuse not blow.

Thanks everyone who added to my Post.

Cheers
(Love this place)

 

You will not see 12 v at the right fan connector , hard to get the engine to temp for it to come on

AC pressure switch jumper ?

Swapped fan connectors and Key to on only ?

The Blue wire on the 4 way AC pressure switch to Black / Pink is the AC on enable to the AC control module

The White / Blue is the high pressure switch to the White wire for both fans enable ( 290 psi )

The Red / White wire to the same White is the single fan low pressure switch ( 174 psi )

Water will sometimes get inside the fan control module ruining it if mounted upside down

Ask me how I know

The Black fan control module for the X308 is different then the White one for the X300 with the inline 6 engine

 

That means that there was no short or high current draw by the offending fan; it just stopped running due to loss of contact via its brushes.

If one fan stops running like in your case, the other good fan will not run either in the Low speed mode and will only run in the High speed mode. This means that your good fan was coming on way too late, at 97.5C engine instead of 90C and at 22 Bar refrigerant instead of 12 Bar. This was certainly inadequate for the proper cooling of the refrigerant and proper cooling of the engine. Furthermore, when eventually coming on at High speed, the cooling was done by only one fan. You were lucky that your engine did not overheat

 

Just be careful to monitor operation after the fix ... how much brush material remained? How did you reseal the motor from water? If this is a weekend car that's rarely driven -- sits in a garage ..may not matter much. But -- you don't want a failed motor after a rain storm on a hot day with a DD.

The temp gauge is set up like an idiot light. It looks like a gauge -- but it's designed to sit in the normal spot for a very wide temp range. It's really only telling you when the engine is cold and when it's warmed up .... once it moves into the high part of the gauge .. it's way too hot and the engine is in real danger. Anything above the "normal" is an alert.

The motors pop up on e-bay for around $75 ... the whole assembly is around $200. They seem to be robust as I can only remember one of our group having a problem.

 

Guys here's a rundown off mine from XJR from A to Z since I've owned her.

- I bought her when she was 5 years old from a realtor in pristine condition with 55,000 miles on her.
I own my own business which requires me to be on the road quite a bit and now as of July 30th 2019 she shows 237,651 miles on the odometer.
- To date prior to this overheating issue the only thing I have replaced is the rack for the rack and pinion steering. And that was my fault because where I park I turn the wheels from side-to-side putting too much pressure on the seals.
- Two years ago I was getting some ball joint work done at my local Jaguar Range Rover BMW, non-dealer shop.
I mentioned that that top fan was not coming on. My mechanic said it comes on when the motor reaches a certain temperature. So for two years I have been putting on thousands and thousands of miles with a dead fan.
- Three weeks ago I started blowing hoses. I called the authorized Jaguar dealership to find out if they have a hose, which they did @ $385 for that hose assembly. It was the one going from the engine block to the engine coolant reservoir.
Well I wasn't going to pay $385 for a hose assembly.
The split happened right at the fitting coming out of the engine. I just cut off the over-engineered joint and slid the hose onto the pipe and used a standard hose clamp.
- Then two more hose assemblies blew.
At $300+ per hose assembly.... yeah, you can kind of get the picture.
(Yes, I found them in FleaBay for less)

And speaking of picture... the one attached is of the repairs I made by replacing the section of hose that was bad.
(I'm a sailor and I have been living my dream by living aboard my sailboat for the past 20 years. I always have extra parts and high temperature hoses.)

- The hoses are clear and are reinforced. I noticed no antifreeze flowing through the intercooler. I drove back to my mechanic and had him take a look.
He said the water pump on the engine would eventually push the air out of the lines.. He told me to continue to drive her and the air would eventually work its way out of the system.
WRONG!
I wasn't comfortable with that so that's when I jumped back on the Forum to do more research.
- I identify that the auxiliary intercooler pump had died. Because of that, that's when my hose and engine coolant Reservoir problems began.
- I did replace the Coolant Reservoir because it's split due to the high pressure and temperatures.
And I did a few MacGyver repairs on those hard coolant line fittings that broke.
- And I custom manufactured a thermostat bypass hose. No one locally except the Dealer had one. I was able to cut a 90° section out of a longer hose and made it work.

- okay that was a lot of words to get to answer some of your guys questions.

- I took the fan apart, cleaned all of the graphite out and put it back together again just like the factory. There were no seals. I did make sure everything fit back together tightly.
The brushes need to be replaced very soon.
- I do understand the dashboard temperature gauge is nothing more than a fancy idiot light.
Having a temperature gauge that reads real-time temperature would be amazing. Not sure I'm going to throw extra money at that at the moment.
- Also I lost heat for my heater.
The auxiliary pump is perfect. The heater control valve has died. One on the way.
So for the moment I have simply bypassed the heater core. BTW the heater core is as clean as a whistle.

- Truly I'm very lucky I didn't cook the motor over the past couple of years.

- Everything under the bonnet is working properly as from the factory. She was built November 2002. She has a XJR 100 badge on the boot. But she is not a true XJR 100.
I didn't put that badge on and it looks like it came from the factory that way.

So for now it's time to do a little cosmetic work. I hit a deer last fall. Crushed the driver's side headlight assembly. I have worn out the driver's seat. And the headliner.... is what headliner is after 16 years.

Thanks guys for everything.
Love this place.

 

Yes -- some of the hoses are only available as full assemblies .... they are expensive. All the small bleed hoses are available -- they are cheap -- just posted them in another thread today. The bleed hoses get very brittle and can snap -- It's one of the few preemptive items I have done to my X308's.. I really don't think the SC pump was your overheat problem. The fan not working is a much bigger problem. That's why you had the hoses popped and the tank cracked IMO.

I have two 02's -- but mine are baby miles next to yours. One I bought new is now at 75 k and my other from the original owner a few years back is at 40k

 

There are two schools of thought when it comes to mileage on a car.
those who brag about low miles and then there's me... :-) LOL

I remember when I first bought my XJR with only 55,000 miles on her I said to a woman that was admiring the car that I need to get a daily driver, not this one.
She changed my life with her reply.

She said......
"Do you like driving the car?"
Naturally my reply was, Yes.
Then she rocked my world. She said, "I've done the math. We're going to be dead longer than we are alive. So if you enjoy driving that car, drive it every single day."

I've used this expression since I was about 18 years old, "Everyone dies but not everyone lives."

Put those two life philosophies together and that's why I have 237,000+ fun-filled miles on my supercharged Jaguar XJR.

it's kind of fun to be on the opposite end and bragging about how many miles are on the car.
It's priceless seeing the look on people's faces and them shaking their head in disbelief when I tell them how many miles she has on her.

Cool beans on your two Cats.

 

Actually put most of the miles on the car when it was new .. put almost 100k on my 95 VDP and had about 75 k on my 98 VDP was totaled in 01. I have more seat time .... just three cars! The 40k garage queen is for the future .. grew up with Jaguar XJ Sedans .. I want one in my life as long as I can drive. My life changed a bit and it was SUV to the mountains or wagon to the beach .... Jaguar became garage ornament most of the time.

 

I love looking at the pics people post of their beauties.

My Lovely Bride tools around town in this '04 Full size HSE.
Some may say we are a glutton for punishment. LOL
Her ride covers our "truck" needs.

Thx again to everyone that have contributed to this thread.

 

Had an 02 and it's up there with my W140 as most problematic vehicle ..... My 95 VDP replace the W140 and a Cayenne replaced the RR. Thankfully ... lease it. The steering wheel came off in my hand after one of the many services. Had a great interior.

 

But wait, there's more! LOL

- The fan I repaired was not really an honest repair, just cleaned.
- She's dragging, not popping on without a little help from my finger to get her whirling away.
- A proper repair would consist of replacing the brushes. Yeah, easy to do but it don't have the time to order them and wait. My Cat needs to be on the prowl everyday.
- Local Salvage Yard had what I needed for $75.00.
- Easy out. Easy in. Simple Plug-n-Play.