Hi all

For 2 years I have an extension cable attached in my 2011 XK to conveniently connect my Ctek MXS 5.0 to the XK, as I also do with all my other cars and motors.

My XK has an OEM spec Varta battery installed, 2 years old.

For the first year I had the extension cable attached directly to the battery ports. Then a year ago I changed the black mass cable away from the port and attached it to the recommended mass connector in the boot area, as per official JLR instructions available here in the forum.

The standard charging process with the Ctek has during all that time been flawless, with both extension cable setups.

Now about 4 month ago I for the first time used the Ctek, connected to the extension cable, not in standard charging mode but in Reconditioning mode. After some hours the Ctek stopped the process and showed red error led.

I then disconnected the Ctek and put it back in standard charging mode. First attempt again resulted in error. But on the second attempt the Ctek charged full as usual.

Since the above first error led of the Ctek, I have never again tried reconditioning, but even in standard mode I now occasionally get the Ctek error led and canceled standard charging process. I then usually do a second or third attempt and then it works and the Ctek completes the charging cycle.

Anybody here with similar experience?
Any advise re how to avoid the Ctek error messages/cancel charging process?

And finally, does anyone here successfully use the Ctek reconditioning mode through extension cable attached to mass connector in boot, ie. with battery remaining connected to car?

br,
ter

ps: on all my other cars/motorcycles this ctek works issueless for years and still now, including in recording mode with battery remaining connected to car. Occasional error only when charging the Xk.

 

Yep get the same on my Peugeot when using crocodile clips and the negative isn't grounding properly.

Usually solved by moving the negative/ground around for better connection.

Have you checked your ground to ensure it's not got corroded or else has moisture around it?

 

My CTEK has always been connected that way and, by coincidence, I also ran a 'recondition mode' sequence about two weeks ago, which completed as normal. My car is the 4.2 supercharged though, so IDK if this makes a difference.

 

Is your Varta battery AGM or conventional wet cell? If it's AGM, you probably killed it by using Recondition Mode, which overcharged it at 15.8 volts.

The manual states that Recondition Mode is for WET and Calcium (Ca/Ca or Ca-Ca) batteries ONLY.



Yes, the Manual isn't clear. You can contact CTEK Customer Service and ask if they will cover all or part of the cost to replace your battery.

 

Thanks all

I just checked the connections and started another try charging, for once in reconditioning mode connected to the ports directly. Lets see how it behaves...

I have a conventional wet cell battery: Varta H3 Silver Dynamic 100Ah

On my Ctek, I can activate AGM and Recond mode at the same time (which I don’t do for this battery, but I guess that this would be the Recond mode for AGM.)

br
ter

 

I have a number of CTEK's and have just purchased another MXS 5. As I went through the search for "best price", I checked reviews and was surprised to find a lot of reports of faulty CTEK's as I've not had any trouble with any of mine. This suggests we shouldn't automatically assume the fault is with the vehicle rather than with the CTEK.

Graham

 

ter,
I'm not sure what you meant when you said "... connected to the ports directly." If you connected your CTEK negative ( - black) pigtail directly to the battery's negative (-) post, that's incorrect. Your 5.0L XK Is equipped with a Battery Monitoring System module that is connected to the negative battery terminal. Because of that module, you must connect your CTEK negative pigtail to a chassis ground. Otherwise, damage to that BMS module can occur. That may be the cause of your problem.
Stuart

 

I started switching to AGM batteries in my classic cars a few years ago and found that I would sometimes get random charging errors on the CTEKs. It was very frustrating for a while. Having four of them, I was able to switch the units and cables around and get the same errors, which seemed to point to a problem with the cars or the new AGM batteries. But after much chasing ghosts in the cars electrical systems and testing batteries, I eventually switched to instead of using the CTEK extension cables, I just plug them in directly and run a standard orange extension cord from the wall outlet and that seems to work reliably. The issue appeared to be the CTEK extension cable itself. I could push the wires together, basically shoving them into the plug and as long as the terminals had a really good connection inside the plug, it was fine, but eventually the terminals would work loose again inside the plug and it'd error out. It doesn't seem to be as sensitive to having that 100% contact with lead acid batteries, but it does seem to need a really good contact with the AGMs. So try it with an ordinary 14awg extension cord from the wall plug instead of the CTEK extension cable and see if that fixes it.

Also, I'm not so sure the OEM battery is a standard type. I just recently replaced the original Varta battery in my XF. I purchased an AGM from Interstate Batteries and I swear the new AGM battery case was absolutely identical in every way to the original Varta unit. I had always just assumed it was a standard battery, but it did last nine years.

 

Yes, there's a difference. The Battery Monitoring System module is on the 5.0L models, not the 4.2L models. For the 4.2L, you can attach the pigtails directly to the positive and negative battery terminals. But, as I explained above, for the 5.0L, the negative pigtail must not be attached directly to the battery; it must be attached to a chassis ground.

 

Thanks. I would always connect the negative to a chassis ground anyway. Just a habit I have had for many years. I think it came from way back when I was told that connecting directly to the battery negative for charging could cause a spark and that could be dangerous back in the day when batteries may have leaked more gasses than they do these days. TBH I can't really remember as it was decades ago, but the habit has stuck. Good to know that my habit has directed me the right way with more modern vehicles with these BMS modules.

Only two or three weeks ago, my wife bought a CTEK for her Porsche and she watched me install it for her and asked why I didn't "just connect the two wires directly to the battery". IDK if her car has a BMS module but if it has, and I had done it the 'obvious' way, I guess I'd have fried her battery by now. Weeks of doghouse would have ensued! So thanks for the heads-up!

 

Chucked mine in bin a few month back , Suspected it to be faulty . Never buy another overrated in my opinion . now use a Ring 10amp Charger once a week on the Aston that is hibernating . No problems it shows the voltage the second it is put on a feature the ctek dont have

 

I have had one or two failures with battery maintainers for my motorbikes, the worst being the Oxford Products Optimiser - it had something missing that was known to destroy batteries if there was a power cut - they cost me a lot of aggravation and didn't really want to know - it takes years to gain a customer and seconds to lose one as my old employers used to say.

Interestingly I switched to RING to end my problems - I didn't realise they did car products too. Good choice if they still do decent quality, although a torch I bought of theirs was extremely shoddy - wrong size springs in the battery tray?!? Its the problem with people doing things on the cheap with manufacture - they don't learn, they keep using China