Now I took the following measurements today:
Motor off, Ctek connected for 3 days: 12.36V / 12.42V
Idle cold start 1500 rpm: 13.67V
Idle 1000rpm with light and air conditioning on: 12.44V
Idle 1000rpm without light and air conditioning: 12.5V
Idle 3000rpm with and without air conditioning 12.35V

Then car switched off: 12.47V

I still had half an hour to do something.
Afterwards the battery had 12.7V
Cold start idle 1500 rpm: 13.46V
1000rpm idle: 12.35V

Now I drove the car onto the highway and drove a distance of 50 miles at a speed of around 90 mph with about 3000 rpm and one small traffic jam.
Afterwards I stopped to wash the car. Shortly before the car wash, the screen went black for the first time.

Measured values ​​in the car wash:
Idle: 13.07V
Auto off: 12.5V

After washing the car:
Auto off: 12.36V
Idle: 12.37V

I drove 10 miles home at about 50 mph.
Now the screen went off regularly.
At home:
Idle: 13V-12.8V
Auto off: 12.3V

Now I'm leaving the car in the garage without Ctek and will see about the change in a day or two.

 

All the measurements you just posted makes me think your battery is terminally toast.

 

OP. I just took some readings . Battery at rest , car not used for 4 days ,12.59v. Car started and running 14.1 v. Journey of 52 miles , no radio, or climate on , no lights . Battery with car running 14 v. Battery after about 20 mins after shut down 12.67.
Battery is two months young.

I think it's your charging circuit ,your not getting much off your alternator or the circuit.

 

OP. I just took some readings . Battery at rest , car not used for 4 days ,12.59v. Car started and running 14.1 v. Journey of 52 miles , no radio, or climate on , no lights . Battery with car running 14 v. Battery after about 20 mins after shut down 12.67.
Battery is two months young.

I think it's your charging circuit ,your not getting much off your alternator or the circuit.

Also I would put your charging lead on the battery terminal, like you have the positive one.
Final point you battery looks smaller than mine , it may just be the picture.

 

ever since I switched to an AGM battery my 13 XkR-S the battery needs to be completely charged or my instrument cluster panel does a dance for a few seconds before responding on startup. I think the AGM battery is not giving the same startup voltage as the Wet battery used to?? It drops to 8V on startup I think that is low??

 

Amps is the other part of the equation. Load is the big factor but in the case of the OP, his voltage is so poor, no need to test load IMO. In his case, continued testing is a waste of time. Here in the US, any auto parts store will load test your battery free of charge. Don't know if that's the case for him.

 

I'm not thrilled with the values ​​either and will have a stress test done in a workshop.

But the question now is, why is the battery empty?
Is the Cetek defective?
Is the alternator defective and not charging correctly?
Is the BMS defective?
Strangely, the meter shows 13.5V at 1500 rpm. Much less at 1000 and 3000. So it doesn't seem to be loading properly?
With Cetek the battery only shows 12.4V, which is probably too little, but it shows that the battery is full.
Hence the question, why is it not loading correctly?
I'm afraid that if I just replace the battery, the problem will soon recur.
I've already had bad experiences with AGM.
Does it even make sense to install a 100 or 110 Ah battery?

 

My alternator registers mid to high 3s normally, then to low 14s occasionally.

 

I have now charged the battery again with a new Ctek. With the car turned off with Ctek, the meter showed 13 volts. As soon as I disconnected the charger, the voltage was just under 12.4 volts.
Therefore it definitely looks like the battery is at its end.

But that doesn't solve the question of what its the reason for it.

I'm going to buy a new battery and have the alternator checked at service next spring. I can't think of anything else right now.


What do you think about installing a 110AH battery instead of a 90AH battery? (Lead acid, no AGM)
Thanks and greetings
Christian

 

If it fits, more capacity is good!
wj

 

Hello everyone,

I have now installed a new starter battery (110AH). I tested it before installing it and charged it “fully” again with the Cetek. After installing it, I started the car and let it run briefly. The meter showed about 14.65 volts. A sign that the alternator is charging the battery.

I turned off the car and measured again. The voltage slowly fell to 12.28 volts. Can this be? Is that normal?
Did the startup process cost that much energy?
Does the interior lighting, the trunk lighting and the control units that are still active draw so much power or does it have to do with the fact that the battery has not yet been trained?

I connected the charger and the voltage slowly increased again.


On Saturday I'll drive the car to its "winter quarters." Then I'll see how the screen behaves. Whether it stays on or switches off again.

Chris

 

Measure a few minutes after the car exits convenience mode and the trunk light shuts off.

 

My voice guidance on the nav only works once at the start and then I have to tap the speaker icon every time I want to hear a guidance instruction. Am I missing a setting somewhere?

 

Christian, like you, I followed "advice" that battery replacement with an AGM was the answer to all our troubles! Like you, I found the Yuasa AGM caused constant problems for me. I too have gone back to wet cell and put in 100aH Bosch. Sadly, whilst everything else has since worked perfectly, my info screen still goes 'black' occasionally. Fortunately, use of the on/off button seems to rectify things and it then works fine for some weeks.. On one of the UK Jag club forums there was a debate for some time; the screen is apparently made by Alpine (here anyway), and is known to have issues. There is a specialist company who can repair the issue somewhere in UK, I will try and find the link.

 

Hello Drphilgood,
thank you for your contribution. It seems to be the same for you as it is for me with the screen. Unfortunately, it happens to me all the time.
It would be great if you had a link to the repair. I'm currently also excluding the battery. Although I have now installed a new battery, I was no longer able to test whether there was a change before the car went into hibernation.
I removed the original battery and charged it externally. He seems to be flawless. It is still unclear why such poor values ​​are given when measuring in the car. A quiescent current measurement showed 5mmA, a perfect value. This means that no consumer drains the battery while it is at a standstill.
That's why I now suspect the monitor. I'm already looking to see if I can buy a used one. I don't think it's difficult to swap

 

Don't assume the monitor just yet. Your primary issue of a bad battery needed to be resolved before you can diagnose the problem. After bad battery, know that the touch screen is part of a fiber optic loop. There are between 6-8 modules in the loop and if one is faulty, you'll get the blinking screen.
Best to buy a fiber optic bypass loop. They're low cost and you can find them on Amazon. like this:


It's a simple test. Start in the boot with the BT module. Remove the FO cable from it and connect the bypass loop to the FO line. If the blinking stops, the BT module is the problem. If not, move on. The Satellite module is next. Those are two common fail points in the loop. After you've checked the modules in the boot (known as the trunk stack), then move on to the center stack (behind the touch screen). You will have two to check there and you'll easily see them. The CD player and the entertainment module above it.

That's about it unless you have an iPod connection. That module is also in the loop but near the tail light. Lastly, if you have premium audio, your amp is in the loop and that's in the passenger foot well. Neither of those are likely fail points though.

You can swap out parts but if the touchscreen is bad, imo you get a blank screen, not a flashing one.

I would have pointed you to this initially but your battery was clearly bad and you needed to resolve that first.

 

Hello Sandra W,
thanks for the new suggestions. I'll buy a fiberglass loop by then.
I won't be able to check whether switching off the monitor with the new battery has finally been solved until March, as the car is now in "hibernation".
For me it doesn't "flash", but the monitor switches off after a certain time (goes black), then I have to switch it on again, then it takes a few minutes and it switches off again, then switch it on again, ...
Although I have a US vehicle, I replaced the satellite module with a DAB+ module and installed a rear view camera as a retrofit. I bought both from "Cambo" here in the forum.
The conversion took place in 2019. Perhaps one of the fiber optic cables used is now defective.
I can continue my research in the spring. Until then, thank you for the numerous productive tips.
Christian

 

I told you to unplug your bluetooth model like 50 posts ago..!!

 

Sounds good. You have DAB instead of satellite but same solution. Good luck next spring!

Sean

 

I told you to unplug your bluetooth model like 50 posts ago..!!


Yes, I also unplugged the BT module at the time, unfortunately without success.