Hello guys - I have a problem with the cooling fans on my 2001 4L S-type (LHD, Middle East market).

The car was on loan to a pal who was driving it a week or so ago when the temperature started to rise so he shut it off before the "High Engine Temp" warning came on. On investigating, we found a leak from the header tank (expansion tank) from a split in the aged, heat damaged plastic - daytime temps here in the United Arab Emirates are currently 45C+ (115F or so).

The tank has been replaced and the cooling system is now watertight and the correct bleeding procedure was followed. However, the car is still getting hot and it appears that the cooling fans are not running.

I checked the handbook and it tells me that the fan is controlled by fuse 25 in the engine bay fusebox (80amp) but on the diagram of the fusebox on the opposite page there is no fuse 25 - they only go up to 24!

So, the first question is:
where the hell IS the fan fuse on a 2001 S-type?

there must be a relay for the fans but there is no mention of that in the handbook (not that it actually mentions any relays in detail!)

Question 2:
Where the hell is the fan relay or is it part of the "cooling module" on the bottom of the shroud?

I've tried hunting through the illogically laid out mess known as JTIS but can't find any reference to the location of the fuses and relays.Obviously, there may also be a problem with the thermostat but even if that was bad, I would expect the fans to cut in but they don't. they don't cut in with the aircon switched on , either.

On a (possibly) related note, the car will no longer rev past 3000rpm although it was fine until the heating issue.

Question 3; would failed fans (or fan control systems) cause the ECU to go into some kind of limp mode without throwing up a check engine light or any codes?

I should add that although my bluetooth OBD scanner is connecting OK to the car and showing live data on my smartphone I am getting no codes at all. What the live data DOES show me is that even when I floor the throttle with the engine switched off, it only reads 80% throttle movement. With the engine running it is only giving about 22%.

The car is currently stuck the other end of town and I need to recover it but it's currently not driveable due to the problems mentioned above. I plan to try disconnecting the battery to see if that will reset anything and may need to "hotwire" the fans to get the car home. Failing that, I might have to pay to get it recovered to my house but would rather fix it then drive it.

We don't have any independent Jaguar specialists here and the dealer is a) wickedly expensive and b) not known for doing a great job. However, I may have to pay to get them to do a diagnosis and then make a decision about the viability of fixing this car.

Any suggestions? Thanks

 

Question 1: Answer: Engine compartment fuse box - relay 09 - schetmatic under fuse box cover (black fuse w/ clear top - marked 80A) - that is the relay/fuse for the cooling fans.

Question 2: Answer: There is a module on the fan assembly - sometimes these "crap out" - if your 80amp fuse/relay is good - look here next. Possibly, your fan motor could have crapped out also causing your fan not to run.

Question 3: Answer: Yes, possibly.

Did you follow JTIS bleeding procedure - bleed screw near master cylinder w/ heat on max - engine running?

Yes, your thermostat (or possibly water pump) coule be factors here also - but the fan would be running (or should be)

Good Luck and report your findings back to us...

 

Thanks for the answers I'll check that fuse/relay.

The JTIS bleeding procedure was followed to the letter and a good, steady stream of fluid was running from the bleeder.

 

Be careful if you try to hotwire the fans. First disconnect the input as it's PWM. Don't just hotwire or you can damage things that now may be OK.

 

Thanks for the tip. I've not had a chance to do anything else on it (due to work) but will try to get a look at the relay/fuse tomorrow or thursday.

If it turns out to be the cooling module, I've seen them on ebay.com for about $75-80 and I dread to think what the Jaguar dealer's price might be for a new one (the EPC says $528 but here everything costs more than the USA). Specialists can do genuine ones for $350 and Rockauto do aftermarket ones for $200 or so. So not as bad as it could have been (assuming that's the problem)

 

They hardly ever fail. Much more likely to be a bad fuse, relay or some wiring. Read ECT sensor via OBD because if it's low then the PCM would not put the fan on.

 

Thanks for all the help guys - I have now resolved the problem of the cooling fans.

I checked the 80amp fuse (fine), swapped the relays around in the fusebox (in case one was faulty) and unplugged and reseated all the electrical connections for the cooling module and fan wiring. All seemed fine but the fan still didn't rotate, whether the aircon was selected on or off.

So, I deduced that the fan must be seized - so I hit the motor casing with my hammer and the fan started to rotate slowly. I hit it again and it started to rotate at normal speeds and now all is well The temperatures are normal whether parked or driving and the fan work properly after stopping and restarting the car. The only costs are the replacement header tank (the old one split when the car overheated) and a refill with coolant - the tank is an aftermarket one from ebay at about 1/3 the price of buying a genuine one here.

The throttle issue appears to be a separate issue - perhaps related to my other post on throttle problems: https://www.jaguarforums.com/forum/s...roblem-117645/
Although the car won't rev past 3000rpm when in P or N, it seems to drive reasonably well and revs normally when driving. I'll tackle that issue on the throttle thread

Thanks for you help, guys

 

Nice cheap fix!

There's a rev limiter...

 

That would explain it.

Whilst this was ongoing, I bid on a fan, shroud and cooling module on ebay - and won it for £10 ($16). It will cost a bit to get shipped here but it will pay for itself if the fan motor fails again. The cooling module is worth every penny of that (and more)

 

Well the fan motor has seized again so I'm going to fit the replacement fan when it arrives in the next day or two

 

Yes I was just going to say that will be a temporary fix and you should plan to get a fan motor headed your way.
.
.
.

 

The fan arrived yesterday and I replaced it and all seems good.

I didn't follow the procedure in JTIS because that tells you depressurise the aircon and disconnect the receiver/drier which is NOT necessary. What I did was:

Before doing the shroud, I removed the inlet trunking and hoses/wiring to improve access. i also removed the grille so that I didn't damage it whilst leaning into the engine bay.

1. Remove the two triangular radiator top mounts - 3x 8mm bolts each.
2. Disconnect the wiring connectors from the fan
3. Remove the radiator top hose (including the T-piece in the middle of it)
4. Disconnect the small radiator hose that runs from the auxiliary water pump to the V of the engine.then tuck it out of the way.
5. Unbolt the receiver /drier - 1x8mm bolt and push it away to the side.
6. Unbolt the auxiliary water pump from the shroud 2x10mm bolt-headed screws. Push it away to the side, after disconnecting its electrical connector
7. Unbolt the front edge of the undertray and pull it down to access the cooling air scoop for the Cooling Module. Remove scoop/duct
8. Disconnect the wiring connectors for the DCCV
9. Unbolt the shroud from the radiator-2x 8mm bolt
10. Carefully wiggle the shroud up out of the engine bay, taking care with the receiver/drier, the aircon pipes and the auxiliary waterpump and hoses.

If your DCCV is faulty then this is a great time to swap it as the access is good now (well, as good as it will ever get!).

Assembly is the reverse of dismantling - as the old saying goes. Take care not to pinch any hoses or put strain on the aircon pipes. It took me a couple of attempts to get the shroud seated but it was not the most difficult job I've ever had to do. I took the chance to fit some good quality screw-type hose clipes (Jubilee clips as we know them in the UK).

Remember to bleed the cooling system in accordance with JTIS procedures. The whole thing only took a couple of hours (including tea breaks) and saved me the hassle of recharging the aircon.

The fan runs when it should and the temp gauge stays exactly where it should do, so it appears to be fixed (that's tempting fate). As a bonus, I now have a spare Cooling Module.

 

Sounds good! Hope it is