Hello BlownKitty!

Popcorn for facts and wrong assumptions and conclusions?
Do you know more about the cooling logic?


Cheers, catfondler

 

To be honest I feel that the FCM is a bit complex (not to mention expensive) for what really needs to be accomplished. Depending on coolant temp the primary fan needs to turn on (low or high speed), if the A/C is activated (the compressor clutch energized) the secondary fan needs to turn on.

I would strongly prefer to not have both cooling fans running at high speed anytime the ignition is switched on or the engine is running. So are these Chinese FCM's interpreting the CAN bus/ECM signal to mean "all or nothing" and powering both fans continuously at high speed?

 

Of course nobody wants two fans at full speed all the time. It's about 2 x 12 to 15A, it drains the battery and the generator don't produce enough current, especially when idling. And motor warms up too slowly.

Until now it's only Dells assumtion / wrong conclusion / fairy tale - for me.
Unfortunately I don't own a PWM simulator to do a quick test of the China CFM control ability.

The CFM don't have a CAN bus connection (2 wires), so it's not diagnosable. The control line works with PWM, and the ECU have to believe the fans are running at demanded speed.

Edit: And there are no different control lines for each fan. The CFM have to decide which fan is turned on at which speed, depending on the demand signal at the control line. And the ECU have to decide, wich demand it sends, also dependent on A/C off/on + chosed power [e.g. "LO"].

Edit 2: By the way, this is my PWM signal, mostly all the time:


CFM PWM signal


Cheers, catfondler

 

Hey Dell!

Please look at this thread:
https://www.jaguarforums.com/forum/x...nition-246633/
(Observation and evidence of regulation by CFMs from China.)

Perhaps you've an idea abaut root cause of ECM demands fan at full speed.


Thanks, catfondler

 

Thanks but no thanks, I'm done.
Made my point, the rest is perception and debate. So if you want to see why your Asian CFM's run full all the time (which some do, most don't even work), give up and install the correct OEM one in and watch it work correctly. Dealt with a guy like you 3+ years ago and he finally gave up. Ordered an OEM after 3 Asian ones and = what do you know, it worked!

Want more insight? Contact member Dr Dome who parts out X's. He agreed with my assessment of the "high side" failure on my FCM. Bought one from him for replacement and works perfectly.

 

Hi Dell!

Maybe there are some disfunctional asian dummies out there. (Or wrong models ordered. Or other failures around the CFM like loose female contacts in a plug.)

My both CFMs from China (second one bought at 25€ incl. shipping, first one was previously mounted from another shop) are working basically (proven in the other thread).
Both are 3-pin.

The transmission fluid temperature sensor has a failure and causes the ECU to demand fan full speed.


I originally thought your opening post was very good. Unfortunately it led me on the wrong way (I stopped my search for defective sensors), because it is excessive or wrong.
But by accident it led me to the loose contact problem, and to the possibly desoldered solder point (because of heat from the loose contact).


Cheers, catfondler

 

Hello fellow X-Typers,

In the interest of sharing thoughts and knowledge, the very foundation of these forums to allow people from all walks of life to engage constructively in sharing their enthusiasm for these cars, I will humbly offer my theory of operation of these controllers as I continue to build my own understanding. We are all trying to help each other remotely without the advantage of being able to lay hands on the subject cars ourselves.

Looking at the schematic I have for my 2005 model, the FCM has two supply lines; an ever 12 volt line and an ECM controlled 12 volt supply. There is the obligatory earth and four output lines (two to each fan motor).
The only speed control input is the pulse width modulated (PWM) control line from the ECU.
The FCM no doubt internally also employs pulse width control management to the fan motors via its output transistors (FETs).

Now this is where it gets really intriguing to deduce how the FCM can internally work.........with only one actual control input (PWM) the fan control module internally must have its own small micro processor that is coded to recognize and react to various thresholds in the received duty cycle (on to off ratio) of the PWM signal sent by the ECM. Remembering that the ECM is receiving inputs from all the sensors such as water temp, intake temp, trans temp and vehicle speed etc. to deduce what fan speed is required, thus what PWM ratio to send the fan control module.
For example (I use generic ratios in this hypothesis - not measured or proven) for the PWM lower range of 3% on 50% off, the internal processor will react by turning only one fan on, The speed of that fan will most likely be controlled by the variation in the PWM within that initial 3-50% range.
Then when the PWM input crosses the predetermined programmed threshold (say 50%) the second fan will be engaged by the FCM processor and begin its speed increase up to the maximum when the PWM input reaches maximum 97% duty cycle - resulting in both fans being at maximum speed.
Now the FCM also likely has an internal Eerom that stores local data such as typical fan demand behaviour which is formed by engine and transmission performance, driver behaviour, climate effects and geography. The micropreocessor will call on those parameters to set up its internal biasing against the manufacturer's default PWM table data to tune the FCM behaviour. Thus the module learns the motor, transmission and external demands being placed on the cooling system and learns to respond accordingly.

The dual supply lines likely enables the FCM to properly understand when the car is running and when it is being shut down, hence the ability to decide whether to run fans beyond engine shutdown with an internal timer function of the processor based on ECU PWM output at time of ignition switch off.

I would suspect the aftermarket modules may omit some of these behaviours and be less subtle in overall fan control with respect to the original controllers.

The coils Dell refers to will be part of the noise reduction filtering out to the motors and also stopping the harmonics generated within the FCM back-feeding into the car's main electrical supply and causing excessive noise disturbing other modules/systems and possibly creating audible interference in the the entertainment system.

A quite complicated little module for sure, but I suspect there is something quite elegant in the way it works, pretty much the way I think about these cars in general.
Thanks to you all for reaching out to help total strangers, long may it last!

 

Hi Mark!

The basic ideas about this fan speed regulation are pretty much correct, I think.
But no micro processor.

A much simpler, more analouge PWM control, I think. Perhaps a small programmable logic, like a FPGA.
You'll find several discrete PWM fan control schematics on the web.

There's no logic in the CFM to learn about demands. That's (the overrun of the fan) simply controlled by the ECU and ACCU/CCM.
ECU isn't switched off when you turn off the ignition. The control units gradually shut down.

Below pictures of my previously mounted, probably Chinese (no label stucks on it), module, a probably more original (or more older variant of) module (probably Ford Mondeo) found on the web, and a third/fourth one (Ford Mondeo Mk3, 940.0041.01 [ 3-pin !!! You see it, Dell !? ]).

I needed some help here. But now I only had / will help others with my experiences.
The help I got was jagrepair.com with it's schematics. And a found info somwhere about possible sensors on which the Ford/Jaguar ECUs fan control depends on..
And knowledge about Dells prejudices about Germans... (by the way: inventors of Otto and Diesel engines) And his sadness about his German ancestors (great grandmother)...

Without schematics I wouldn't been able to solve the root problem (perhaps only the loose contact problem).


Dell made up that all "cheap" Chinese modules are dummies / crap. Inwardly, he denies the very likely fact that all modules come from China anyway, including original from Jaguar (= Ford, now Tata from India).
He think dual fan control modules which are used in thousands of at least Ford, Jaguar, Land Rover, and Volvo cars (probably since 20 years) are only created as dummy spare parts from Chinese fraudsters. How likely is that?

Much more likely for his experiences and descriptions are mistakes in the selection of the right spare parts, installation errors, or additional failures on the car.
The observation that a module did nit work as expected when it was installed does not in principle say anything.

But presumably he only is an employee of a dealer with USD 300 modules...

Sorry, Dell, I'm angry about your posts, now. Pure China bashing, technically unsubstantiated, and stealing a lot of my time.
If you weren't so ignorant and arrogant, you could have learned something from my case and my work.


Cheers, catfondler


my previously installed module, probably from China



probably Ford Mondeo



Ford Mondeo Mk3, 940.0041.01



Ford Mondeo Mk3, 940.0041.01 - 3-pin !!!

 

I only have two questions::

1. Does the Chinese/aftermarket FCM/CFM ONLY have 1-speed (high) for both fans?
and
2. Any time the ignition is on do the fans run non-stop at high speed?

 

No. The speed is variable, of course. My Chinese CFMs are running at the demanded speed. (Wheter the speed is 100% like original, I don't know. But I guess. It's not that difficult to realize a speed profile depending on a PWM signal.)

Look at my thread: https://www.jaguarforums.com/forum/x...nition-246633/

So far, I haven't tested whether one fan start first, and if the demand is higher, the second comes in. Or whether both are controlled at the same time.
(The reason for a number of 2 fans is pobably not the performance, but the smaller height of the assembly.)

No, usually not. Only if another cause causes the ECU to demand full speed. (Like my defective transmission fluid temp sensor.)


Cheers, catfondler

P.S. What about popcorn, now?

 

Thanks for the answers catfondler, and I just read the latest information in your post.

Regards, BK

PS With or without butter?

 

The original FCM manufacturer is Gates UK (fcm134). A division of Gates in Colorado (est. 1911).
​​​​​Module taken apart =

 

Hi Catfondler,

There is a lot of help in these forums, and everyone is trying their best to assist total strangers.
I have a huge amount of respect for the senior members and others that day in and day out offer up their hard won knowledge to those of us that have only recently joined.

I think the best approach is to treat these forums like a hospital visit.....leave your pride and dignity at the door, take what help and support is offered which is freely given in good faith.
We are no doubt walking the hospital corridors with our butts showing through the gap in the hospital gown and nobody is pointing and laughing!
Classic rule.......Don't p**s off the nurses and doctors and your stay will be a pleasant one.

Glad you found the solution to your problem being the transmission temp sensor sending a false reading to the ECU.

 

This is so fraking funny. This is Jaguar Corporation response to my inquiry on precisely how the FCM functions technically =

Thank you for contacting the Jaguar Customer Relationship Center regarding the X-TYPE Fan Control Module.



As we are not licensed mechanics, we do rely on our authorized Jaguar retailers for their technical experience and expertise with these queries.



Should you have any additional questions or need assistance in locating the nearest authorized Jaguar retailer, please contact the Jaguar Customer Relationship Center at 800-452-4827, Option 9, and a representative will assist you further.

 

Hey it's not like the factory will be busy building cars currently with the chip and base material shortages that are going to plague production schedules for months and years to come..........
Back to analogue instruments, manual transmissions and carburetors anyone?

Saw a CNN item two days ago about an elevator manufacturer in USA saying his carbon steel sheet metal used to be 45c a pound, now $1 a pound due to supply issues.
Their stainless steel normally arrives within 7 days of order, now seeing 2-3 months lead time on orders.

The knock on effect is going to be huge.......
Keep up your maintenance on your X's folks, I think we might be enjoying them for a while yet!

B.T.W take a close look at your whiteware: ovens, cook tops, laundry appliances etc. as they are going to be suffering low production quantities as well.

 

Lol, another Australian colloquiallism. "Whiteware"

We call them "appliances" generically

 

Sorry, Dell, but Christchurch is in NZ (not Australia)....

 

Yeah, noticed that but the colloquialism still stands :-) :-) :-)

 

Is is not "PC" to call your laundry and kitchen appliances Whiteware these days?
Of not, then I need to stop calling audio equipment and TVs Brownware as well !!!

Well there goes 40 years of an electronics servicing career down the gurgler.

 

Well, I have never heard them called 'whiteware', but we call most kitchen and laundry electrical items 'white goods'. I really have no idea of what they may be called in USA and, as I doubt I'll ever need to, I don't care much.