That fault is just a missing message fault, in this case in your TCCM, transfer case control module, meaning it didn't get a message it expected from another source on the network. Usually those we ignore unless there's an active problem. If you have a way to see the snapshot data, it will show what message and from what module it was coming from.

 

Is that ECT2 temperature of 25C shown on your screen at cold startup or is the engine warm?

And hold on, we didn't realize ...

"The air conditioning system was also cleaned, but that didn't turn out to be the cause either."

Can you tell us more about that?

 

The air conditioning system was cleaned and recharged yesterday at Jaguar. There has been no improvement; the fan continues to spin at a very high speed as soon as the engine is running. The ECT 2 value was measured after approximately 10 km of driving, and—with an ambient temperature of 22 degrees—it registered exactly 25 degrees. The ECT 1 sensor was at 91 degrees at that moment, while the engine oil temperature stood at 75 degrees. In my view, this is unrelated to the issue; during a cold start—and until the engine reaches full operating temperature—these are normal values, provided the thermostat has not yet opened (which presumably occurs when the ECT 1 value reaches 95–100 degrees). Only at that point does the main coolant return circuit open.

 

Code U0001-87 is perhaps from my HP Tuner Gear Software and i have this Code since after the Software Update since 3 or 4 years. I cant remember
when i make this update. I believe that is not the problem.
The Fan have 4 wires, red, black for 12 Volt and the Data wires white and green for pwm. The pmw signal is in my view the same logic as in my job the LED Driver dimming signale pwm to the LED Modul..
I can ask my technical team here in the office, how can i test this two wires green and white.
I assume that if the system detects an incorrect or implausible value, the small controller located within the fan housing immediately switches to full power for safety reasons. Since this reaction occurs almost instantaneously—for instance, yesterday when I was backing out of the garage with a cold engine—you could perform a quick measurement right at the cable connector to check what signal is actually being received there. For added assurance, you might also want to measure the 12-volt lines (red and black); you should certainly be able to measure a constant 12 volts there.It's a good thing the fan is running too fast—better than too little ventilation!

 

next step for the weekend, we testing with an oszi the pwm signal, what comes from the ECM. My colleagues told me, you can do this also with an digital
multimeter with HZ % DC feature. the multimeter will set 0-100% and you can see what comes over the time in the first 5 minutes.

 

Correct, you can check the PWM with a multimeter. Base 'off' signal to the fan is about 9%, more than that it starts to come on and go up in speed. If it loses that 9% signal, it goes to full speed as a safety measure.

 

ah perfect, This means I just measure the white and green wires with the multimeter, set it to %, and then I should be able to see what is reaching the fan?
Do I need to pay attention to whether the black or red lead from the multimeter is used to measure the white or green wire? Or does that likely not matter?

 

Does the ECT2 ever come up to operating temperature or does it stay at 25C?

ECT1 is at 90.86C so the thermostat should be fully open and ECT2 should reflect that temperature as well - am I missing something here?

ECT2 may be the problem.

 

It would depend on your device but I don't think it matters. I would go red lead on the PWM wire, and black to ground, just to make it simple.

 

Min 95-100 Ect1 and the Thermostat will Switch to open in my View

 

I agree that this is an issue. The ECT2 will be less than ECT1 when warmed up, but not 25c, that's far too cold.

 

Try putting the car in dynamic mode, I believe that opens the T-stat earlier.