Edit: Sorry for the double posting - meanwhile my original post is released by an administrator.


Hey guys!

2006 X-Type 2.5 L AWD, sedan

I need some help: the radiator fans run at full speed during ignition-on (with a little delay after turning on, and differnt delays after turning ignition off).

The Cooling Fan Module (CFM) is controlled via a PWM control line from ECU. All the time ignition is on (also if motor is running) I see the following control signal:


PWM from ECU (about 0.2 to 15.30V)

It's about 93% high and 7% low.
(The control line is 100% ok because of the 12V comes from the CFM, and the ECU pulses it to ground.)

I assume duty-cycle of 93% high means full speed, but i don't know exactly. It maybe be vice versa. (At a certain BMW it is vice versa definitively.)
Does anybody know it exactly?

If the ECU demands full speed intentionally there have to be a root cause. I've to find this root cause.

I've checked this until now:
- coolant temperature: plausible
- air intake temperature: plausible
- fuel temperature sensor: expected resistance
- engine oil temperature sensor: expected resistance
- A/C pressure sensor (A/C off): about 1.0V (from 0 to 5V, according to wiring scheme)
- (climate control) evaporator temperature sensor: expected resistance
- (climate control) discharge temperature sensor: expected resistance
- coolant level switch/sensor: not available / not applicable / not installed
- coolant level: satisfactory

Does anybody have an idea of another failure which can cause all time full speed?


Cheers, catfondler

 

In the "2005 MY X-TYPE Electrical Guide.pdf" I discovered this description: "COOLING FAN MODULE CONTROL: PWM 140 Hz, POSITIVE DUTY CYCLE RANGE 7% - 95%".

(I've read at other source: below 7% and above 95% the fans are running at full speed, too.)

So you can see about 93% duty-cycle in my oscillogram (if I translated correctly). Right? Just as I thought. No surprise that the radiator cooling fans are running at full speed.
(Both of my CFMs from China [the previous mounted one, and my new one] behave es expected, at least in this operational situation.)

Now I've to look for the cause of full speed demand.

Ideas are welcome!


Cheers, catfondler

 

I interpret your PWM signal as going to ground for very short pulses and is trying to tell the FCM to run the fans slowly or off.

When Jaguar says the fans are to run full speed when the PWM signal is outside a certain range, it's saying a properly working FCM will run the fans full when it sees no PWM signal at all. That is just a guess. If that is the case, I would be looking more at your FCM than your ECM.

My 05 X-Type has an old style FCM and the fans never run. I have a Beck/Arnley 203-0291 FCM, but have not installed it yet. It has 8 pins and I expect (hope) it will work fine.

 

Hello bigdiver!

Yes, it might be vice versa, like you'd written. But we are not sure.

So new consideration: A PWM duty-cycle of 93% does not necessairily have to mean a fans speed of 93%. It could be vice versa.

Here at a video from Scanner Danner (long) of a Mercury,

a description of Pico Technology of a BMW,

and and a video from MrGreasybob of a Ford Crown it seems to be vice versa.


Now I'm as far as I was before.


Cheers, catfondler

 

Hey guys, now I'm on!

My two CFMs from China are operating.
"Duty-cycle = high" means "fan speed = high".

The demand of full speed comes from the ECU / car. - But what causes it!? Any help is welcome!


ignition on, engine off (~12.5V), A/C off
duty-cycle abaut 93%
fan nearly full speed


engine on (~15,30V), A/C off
duty-cycle about 93% (6.5 DIV of 7)
fan nearly full speed
2 pulses in (7 * 1 ms/DIV =) 7 ms
(7 ms / 1)-1 => ~142 Hz:



engine on (~15,30V), A/C on (+ "LO")
duty-cycle about 71% (5 DIV of 7)
fan speed slower (for a period of about 25 to 30 seconds):



Cheers, catfondler

 

Root cause found: Transmission fluid temperature sensor (FTS) is on 1,67 Ohm (corresponds to approximately 108°C) at about 20 to 30°C transmission temp.


Cheers, catfondler

 

First, kOhms was meant, not Ohms.

Second, I guess I was wrong.
Dell Gailey posted a link for an ATSG / Mazda Technical Service Information on the JATCO JF506E Transmission here.
By the way: VW used this JATCO transmission as "09A" and "09B".

At page 10 there is another temperature / resistance table. 1,67 kOhm are about 30°C (about 20 to 30°C was my test condition).

The table I used was from a Jaguar student guide of V6/V8 EMS of 2001 (881 Manual-9-5-01.pdf)
I'm assuming this contains a bug or describes a different engine / transmission.

So it's more likely that the problem is elsewhere.

Unfortunately, I cannot read the climate control unit.
And also not live data from the transmission control unit (TCM).

(I've measured all of the climate temperature sensors and the refrigerant pressure sensor, but I don't know if the CCU is getting data from them. [E.g. wire break.])

Which payable diagnostic solution is most suitable for my climate control unit and transmission control unit (MY 2006)?
IDS / SDD, version, interface?

(Is climate control unit only approachable via MS-CAN at pins 3+11 on OBD connector?)


Thanks, catfondler

 

check white/blue wire in plug to fan control unit, it carries the pwm signal from ecu. if its broken the fans will run at full speed, mine was broken within the wire covering so give it a pull and see if it comes apart.

 

Hi x_type_lpg!

Thanks for your idea!

The control line has already been checked with an oscilloscope and the speed control works.
(Is already described above.)

There must be a reason why the engine control unit is intentionally requesting high cooling capacity.

Cheers, catfondler

 

What is your ECT sensor (resistance measuring?
I checked mine and with a cold engine (about 15 degrees C) resistance was 4350 ohms.
Bringing the engine up to normal operational temperature (assuming around 82 degrees C - fans not called in yet) the ECT then measured around 260 ohms.
Just wondering if you have an out of spec ECT.
Can you unplug the ECT and put a 4K7 ohm variable resistor in the two way connector instead and then see if your FCM will operate normally.
If you have about 4K ohms input, FCM should be off.
Bringing resistance down to around 250 ohms might start to trigger FCM to come on with single fan, and even lower resistance should start to call in second fan.
Haven't checked the EOT sensor cold versus hot resistance.

 

Hi h2o2steam!

Thank you for your ideas!

I was able to read the ECT sensor with the diagnostic tester, temperatures were plausible.

But it seems like I didn't check the EOT sensor at all. I still remember looking for him, but I didn't measure him with multimeter. I actually forgot. (My diagnostic tester did not display it live. <- I had noted that in my protocol.)
Awkward!

Thanks to your hint I'm looking for the protocol / EOT sensor!

Edit: Now I remember - someone wrote which sensors are involved in controlling the radiator fan. The EOT sensor was not included.
(Of course, I don't know how credible that is. But my intention at the time was to at least test all temperature sensors ohmically.)
Today I found a thread which describes EOT is only involved in switching under load. Credible?

I'd to wait for Mongoose clone and IDS/SDD...

catfondler

 

By the way: Good description of the CFM function. Thanks!

In this way, after finding the fault, I can also check the new Chinese CFM for correct function.
(Even the old one seems to be a Chinese clone. No Jaguar/Ford label. But at least the old one reacts to changing PWM control signal. Unfortunately I tested it only with one fan connected. [Both fans at most at full speed were annoying.])

catfondler

 

News from the car:

I checked the car with a SDD.

Meanwhile the CCM (Climante Control Module, ATC) is changed to an used one. The defrost damper actuator (definetively ok) has had a permanent error stored, not clearable (strange).
Now this part is running as expected.

But the defrost damper actuator DTC didn't cause the full speed of the radiator fans. They are still at full speed.

By the way: both radiator fans are connected parallel inside the CFMs (my both Chinese ones).
At least I measure 0 ohms between the respective tabs of the two sockets. (I don't want to open the new one to trace the circuit boiard traces.)
So this description couldn't be correct (alt least for X400 of Chinese [or Ford?] CFMs?):
Unfortunately, the plug of the radiator fan that was left connected has now melted due to the endurance run (as an additional problem).

Unfortunately the search has to go on.


catfondler