I've now a couple of times tried the CA-146C adapter that came with the N900 (old round Nokia charger plug to MicroUSB) in my car with the Insmat phone charger I use for older Nokia phones. The light on the charger comes on, the N900 thinks it is getting juice, but the battery seems to be draining the same speed as if though there was no charger attached. And I have BatteryGraph data to prove it. A friend has had exactly the same experience with this adapter.

My N900 charges normally with the wall plug adapter, or via a MicroUSB cable from a computer, so it's unlikely this is a problem with the phone itself.

So, is the CA-146C just an decorative item with no real-world usability, are there a lot of defective units around, or what is going on here?

I've tried to charge my N900 with the CA-146C adapter several times today and I didn't get any charge to the battery.

With the smaller Nokia charger plug I got a message that its charging, but battery level indicator never went up from one red bar. And only thing that happens is that the CA-146C adapter heats up.
With the bigger Nokia charger plug I got a message saying "now charging" and few seconds after that error message "charging error".

I've not had any problems with mine... large and small round-plugged adapters from the mains, in my car and via USB have all successfully charged my phone - through the adapter.

I use mine every day since December, '09 with a wall charger and have had no problems. I have also used it with the Nokia car charger that I got either with the N800 or with the N800 Wayfinder mobile kit. I can't remember which right now.But again, no problems.

What I can't do is use a USB car charger to a Nokia USB to small pin adapter (CA-100), and then the CA-146C. Even a desktop USB connection doesn't always light up the N900...

With all that said, to answer the question about whether it is just a decorative item, no. It is useful in my "real word.

However, I have seen pictures of ones that have melted so I suspect there is a bad batch.

If you are having problems with it charging when using either a standard Nokia car or wall charger or you fell that is heating up excessively (warm is ok), My advice is to stop using it immediately.

Motorola and RocketFish make car chargers that fit the N900 and that I used, both work well, and both are about 2/3 the cost of a Nokia one and may be easier to find depending on your location.

The Motorola unit I use even has a push button LED flashlight on the USB end. The RocketFish is smaller and has a shorter, lighter cord that may put less strain on the N900's port.

Mine lasted 2 days on the road then stopped charging. Phone said it was charging, but battery level never rose. Noticed it didn't get very warm once it stopped working.

Binned it and bought a couple of incar chargers with the right plug. One 'Hama' branded, the other I dont remember, both work fine.

If you get a chance and can look up and post online the exact names/models of the chargers you have that do work, that would be much appreciated. Thank you.

Mine seems to work if the N900 is at half charge or better. If it has less than half charge it indicates "charging" even though it is not.

This is one of several ways the N900 has burned me badly. An important business call was prematurely terminated when the phone ran out of charge even though it had been "on charge" all night.

The N900 is a difficult child, you love and cherish but know it will let you down every so often.

Maybe my beloved N900 will come of age when Meego is ready.

Use the search Luke!

http://talk.maemo.org/showpost.php?p=485357&postcount=4

The Covertec kit was like this one I think. It has nine different 'ends' for different devices, with a cable and mains and 12V supplies. It cost a packet, about 30euro IIRC, and they are too tight or stupid to include a small cloth bag so you dont lose half of it

I cant find any pics that look like the Hama one. I bought both in a french supermarket hoping one would work, after struggling to keep my phone charged for most of a 3000 mile drive.

I normally charge my N900 overnight using older Nokia charger ACP-12E(800mA output) via CA-146 adapter. Charging takes ~ 2.5 hours. I tried to use AC-3E(350mA) with the idea that charging will take longer and thus the battery will start draining later so I will get few more hours autonomy, but with that charger charging almost never ends. Phone stays connected to it like 8 hours with green LED light not appearing. And the same charger was filling up my E61(1500mAh battery) for 4.5 hours. CA-146 gets warm when charging N900 with AC-3E.

PS. I have noticed that charging with ACP-12E instead of default charger that came with N900 tops up battery closer to 100% before green light shows and charging stops.

I just had the phone plugged overnight to an Nokia thin-plug Nokia wall wart charger (890 mA) via the CA-146C, and the phone did stay charged through the night. So, I'm beginning to suspect that the old Insmat car charger and the CA-146C just don't like each other.

Update: I looked closer at the Insmat, and it says it only delivers 500 mA. This could well be what the problem is! I'll get a new 1000 mA MicroUSB charger for the car, let's see if it works any better.

Further update: Interesting, Nokia's own MicroUSB charger only delivers 550 mA. I now have a Nokia round plug charger DC-4, which is also supposed to deliver 890 mA, let's see how well that works in the car with the CA-146C and the N900.