30 May 2012

Back on the road, better than before

Main Screen for the Think Tech Center diagnostic tool
We bought our first Think City EV a year ago at full price and have had no problems with it.  Initially Think did not want to sell me a car since I lived so far from any authorized service.  But I convinced them that I was capable of handling any service on my own.  After the bankruptcy and sale, the new Think North America organization started selling the remaining 150 or so cars at a steep discount.

Replacement Power Conversion Unit
When our second Think City EV arrived, the Power Conversion Unit (PCU) stopped working the first day we drove it.  As I reported earlier, Think's service manager stopped by my house a few days later and diagnosed the problem.  This put to rest any remaining questions about service.  Within days, a replacement PCU arrived with the diagnostic tools needed to reprogram it for my particular car.

Bottom view of the installed PCU showing black low pressure coolant hose.  The main 400 volt cables are orange.

I removed the hood, wipers, air intake, vacuum pump and a few other minor items just so I could look over the job while reading the manuals.  This way I had a good idea of what needed to be done before explaining the project to the shop technician.  Then we had our red Think towed to an independent local shop which has demonstrated interest in EVs, and the real work began.
Think City EV engine compartment after removing the hood, vacuum pump, wipers, air intake, etc.
The shop had to disconnect the 12 volt battery and the 400 volt battery before evacuating the R134a refrigerant from the air conditioner.  Then they removed the condenser to gain access to the PCU.  Next the wiper motor and mechanism had to come out.

Wiper mechanism is off to the side
Numerous other little things such as draining the coolant from the PCU and motor, as well as removing the mounting bracket from the cabin heater had happened before we got to the final bracket in the way of the PCU removal.  The technician told me the manuals did not explicitly mention this bracket, but it was certainly obvious enough.

Soon everything was back together and the Tech Center tool was used to reprogram the VIN and teach the new Vehicle Control Unit to recognize the wireless key fobs, without which the car will not start.


Although I was initially instructed to reprogram the PCU completely, I questioned this since the PCU appeared to be a refurbished unit.  Think agreed, and told me to leave the existing programming if it worked.  This turned out to be a fortunate event, as the programming in the PCU appears to be newer and a noticeable improvement, especially for highway driving. 
Live data read-out from the Battery Management System

More about that in a future post, after I have time to plot the data I took comparing both our new and old Think EVs.  I then returned the PCU and diagnostic tools, but only after getting logs files of the Live Data shown above and below.
Live data read-out from the Power Conversion Unit

The discussion list for the Think City EV over at Yahoo Groups has been very active since the price drop.  There have been some relatively minor problems compared to mine, the worst of which might be a bad 12 volt battery.  Think service quickly provided a document (now posted over at Yahoo Groups) which details replacement procedures for the battery.  (I don't know if this particular 12 volt battery replacement was done at the dealer or by the owner.)  There have also been some loose battery cables.  The speculation is that the factory disconnected the 12 volt batteries when sales slowed after the bankruptcy, and a few were not reconnected tightly before shipping to the buyers.  At these prices, most of us are not complaining very loudly about such things.
Rear torsion bar suspension
I have now seen more of the inner workings of a Think than most drivers ever will.  And on the positive side, I may have one of the first releases of updated power and regeneration curves.  Hopefully these new curves will become available as the new engineering organization in Munich gets up to speed.

There is also a survey going on at the discussion list to find out how many owners might be interested in purchasing the diagnostic tool.  Think is getting ready to place an order with the supplier in England.  I am not the only Think owner who lives far from an authorized service center and wants to own a service tool.  As I understand it, it is possible that the price may be lower if enough units are purchased all at once.  What the survey leaves out is that there might be an annual software maintenance fee for the most up to date versions.

09 May 2012

The Electric Car Factor

(The following is a guest post by Lanny who bought his Think on April 19, 2012.)

EV gathering in Marlyland
The area around Washington, DC has a thriving community of EV enthusiasts. We have the Electric Vehicle Association of DC which has been around for over 30 years and pulls a good crowd to the monthly meetings. New groups are forming, such as the Capital Leafs and the Maryland Volt Meetup Group, around the affinity for those cars.

On the first Saturday of each month, members of all of these groups have an informal gathering in a small business development called Maple Lawn that has six charging stations and a nice little coffee shop. The gathering on Saturday was particularly exciting because we had a surprise guest. Jim McL and his wife happened to be driving through the area and stopped by for a bit. This blog is a great resource for those of us who are smitten with these fun little electric cars and it was great to meet Jim in person and introduce him to the group.
We had a good variety of vehicles on Saturday. Besides my new Think City, there were a number of Leafs and Volts, a 2002 Toyota RAV4 EV, an electric Ford Transit Connect van, one of the new Mitsubishi iMiEVs, a Vectrix electric scooter and an electric bicycle that Jim took for an EV grin-inducing ride.

One of the best parts of these get togethers is the chance to see other EVs, talk with the owners and compare notes. There was a lot of interest in the Think. Many were surprised how solid the construction is and how roomy it is inside.

Ford/Azure Dynamics Transit Connect EV

My wife and I are starting to get used to the attention the Think attracts in parking lots and at charging stations. We recently met a couple who own a Tesla Roadster and they spoke of "the electric car factor" whenever they plan a trip to the store. They figure in extra time for answering the inevitable questions about the car to curious and interested folks in the parking lot.

Unsuspecting Plug In Prius Owner

Many of our group had unplugged and left for home when the remaining few of us spotted a brand new Plugin Prius circling the charging station at the far end of the lot. None of us had seen one before and we all started walking. The gentleman was struggling with the charging station and suddenly looked up to see all of us converging on him. Our questions began, one after another. Then he told us that this was his first attempt to use a public charging station. He didn't have a card so Jeffrey in our group lent him his. His wife spotted our "cute" Think and asked if it was electric. My wife gave her the tour.


We apologized for taking so much of his time and delaying his shopping excursion. After all, we were just interested in his electric car! This new plugin owner just got his first lesson in "the electric car factor."

08 May 2012

Diagnosis: Replace Power Control Unit

Think diagnostic interface from the back
I got a prompt visit this morning from Think North America's service manager (I am not really certain what his title is, sorry), the day after my wife and I returned from vacation.  He was able to confirm that our second Think needs its PCU replaced.

They could fly someone down here but I would prefer to learn something about the car, so I am arranging to use a local shop with experience in high voltage hybrids.  We need to lift the car and disconnect the high voltage cables, then evacuate the R134a and remove the air conditioning compressor and condenser to get at the PCU.

Think diagnostic interface from the front
While parts for the car are plentiful, I would like to purchase the diagnostic interface, pictured above.  At the moment these are not plentiful in the US, I am told.  The service manager, who is in regular contact with engineering in Munich (he was on a call with them before coming to my home) will let me know when they are available.  The price is above $1000 and the software license which provides updates regularly might be even more, but perhaps I can get an old static copy with some minor bugs.  Since I am far away from any authorized service, I would like to be equipped to diagnose problems in the future after the warranty runs out.

Think Ox concept from Skeie Industridesign Vestfold

I was not able to gather much in the way of news about the future direction of Think, except that the new model will likely be more along the lines of the four door concept than the previous two seat models.


01 May 2012

Break through technology for EVs in 2015

Delphi Heat Pump for automotive applications
Green Car Congress is reporting a new development at Delphi that will significantly reduce the impact of winter heating demand on EV range.

And I am reporting that our second Think City EV got out on the road today.  Temporary tags finally arrived, 5 calendar days (or two working days) after the car itself arrived.

I put 18 miles on it before it died hard.  I suspect the power control unit, we will see.  Better to happen now while the warranty is fresh.  Being an engineering geek, I am rather excited about the prospect of getting to see something under the hood.  My wife on the other hand, is not so excited.  Let's just say I am lucky she puts up with me.  She is starting to wonder if the Think does have something in common with the Mini E after all.  Like being not totally reliable.  I wonder if it is what the electronics industry refers to as "infant mortality", where some semiconductors die early.