Think City 2011, Tom Tank, Power limit, out of the blue..

[cs]

Hello.

On my 2008 Zebra Think I have the Power Limit and Service fault on some occasions.
As I found out in my case it has to do with the 12V net. If the car has been standing some hours after a trip and not been charged, and maybe the weather is cold too, if you then turn on a lot of 12V consumers the fault comes.

In my case it is often the heater (which runs on traction batt, but the pump and the fan not) fan on 4, lights on, and then brake vacuum pump and brake lights, the fault is there. I first wondered, why this sometimes happened if I use the brake to stop. But then I figured out that it always came with lights, the heater and fan on.

If the car comes fresh from the plug, this isn´t much of a problem, but if your 12 V battery is not new, the car stood some hours in the cold and the DC converter has to power all the things plus charge the battery it seems too much sometimes.

In the video I have to turn on a lot of 12V comsumers, even electric windows, because I wanted to cause the fault quickly. In reality it can take some minutes to drain the 12V batt.

My conclusion is, change the 12V battery by times or use the 12V consumers carefully under this conditions.
If I only use the fan on setting 1 or 2 I can drive flawlessly.

Hope this helps

Chris


See the video I made

http://youtu.be/rvK8akO2p_U

[hma]

Hi Chris,

Very interesting observation and nice video

I have not been able to get a exact verification from Think (ex-Think engineers) what is the root cause for the PL- and wrench-lamp
But, I have noticed a similar behaviour on several other gen0/1-PCU-cars, when installing an additional relay in R21-possition. R21 is for automatically DRL. After inserting R21 and setting 'key on', the PL- and 'wrench' lits. Then when 'key off' to 'key on', the PL/wrench is off, and never come back again.
So my temporary conclution is that the PL/wrench can be triggered then there is a high load or diffenance/change in the 12V or DCDC circuits.
I know that there is a problem with the original DCDC-design on gen0/1-PCU. The circuit is allowed for max 100A, which in many cases have caused hw-failure at the DCDC. The fix is replacing some components on the printboard, limiting the DCDC to ~70A max. This task has to be done by some Think-specialists in Norway, which Röhne&Selmer are using.

Br.
Håkon

[cs]

Hello, update.

Yesterday the problem even got worse 

I wanted to drive to a near city and turned on the lights, after used the brake, lights and the pump started and the Think showed the power limit fault again.

Had to drive the whole way with parklights only ...wuhaaa.

At home I could reproduce it and measure, that the sudden voltage drop, under 13,8V while DC Converter charging seems to cause the fault.

Today took out the 12V Battery which is brand Hella 44AH (the original from 2008??), put it on my professional test bench for Lithiums (Nortec BT2000) and ran a test. Discharge current of 20 Amps gave 5.9 Amperehours.
so this batt is finished.

Will get a new 12V batt next days and hope problem will be solved.

Chris

[cs]

Hello, update.

I connected an old but good Gel-Type 12V Battery to the Think. Its standing outside the car with long cables because it is too big. Tested and measured. It goes up to 14,8 V when the DC charges it and keeps pretty stable above 14 Volts when many 12V users are switched on. So the fault seems all to be about the 12 V battery in my case.

Regards Chris

p.s.: here´s the vid

http://youtu.be/xSCOG-d2VNc

[elektrolux]

Experienced a phenomena the other day:

Had just been driving a Lithium Think City, and had forgotten to close the driver side window before I shut down the car.

Tried to close electric window while restarting the car, and there was barely enough power to move the window during the first seconds of start process.

So it looks like there is an initial very high current consumption on these cars demanding a 12V service battery in perfect state.

[cs]

Hello.

News:

Today I experienced the same fault again.

After the Think had been 4 Days without charge and driven only 30 km.
I turned on the lights and some other 12V Clients then pushed the brake and the "PL and wrench" error came up.

At home I could measure that with a lot of 12V clients switched on the dropping below 13.8V under charge from the DC converter (ignition on) caused the failure again. Actually the SOC oft the 12V battery isn´t 100%, so it doesn´t reach the 14.9V with charge from the DC, as with the new one.

I experienced that the 2 electric windowmotors are killer 12V comsumers if the have to work hard (e.g. windows fully up or frozen). That seems why some users sometimes experienced this failure in connection with using the electric windows.

So what can I do ?
Now I have plugged the Think, put an additional 12V battery conditioner on if the car is not used for longer.
I will report in the next days how it worked out.

I have the impression that the Think A306 (my very early model VIN 41XX) doesn´t check and charge the 12V Battery if the car is parked without beeing plugged. The old A266 I own and several PSA Types I knew, observe the 12V Battery and sometimes do a little charge from the DC even while beeing parked.

Chris

[Go-carter]

I have also experienced some funky issues with mine. Almost every time I turn on the car, right after I've had the charger plugged in, the car wont start, and the economy-meter drops to red. So I have to turn the car off, and on again and everything is fine.

Anyone else has this/similar issue?

[cs]

Ahoi !

Problem solved I guess!
The  "new" 12V Battery was weak already !!! 4 Weeks in use ! Arrrrggggh chinese best quality. A friend of mine bought 6 of these batteries and I got mine from him. He told me that several of the batteries were bad, low capacity, high voltage drop.
I connected my old universal home test AGM Battery again (tested before with remaining capa of 42 Ah C5) and guess what happened.

You can turn on all 12V users and the voltage drops just millivolts.

Now I am considering what battery should I buy? Good flooded lead acid or AGM. There is only room for max 44-50Ah which is ok. I am tending to AGM.

Chris

[elektrolux]

Good that it was the battery, and not something more serious.

Check if Sønnac battery SB500 fits the new Think. Its my favorite one for PSA.

[cs]

Hello.Final result: it wasnt the battery, it was a loose ground cable on the PCU ! We tightened it and everything was fine....

see picture


regards Chris

[El rayo]

Good job, Chris!

Hope it's OK that I copy this info to the elbilwiki.