Bob Bruninga, WB4APR lastname @ usna.edu
This page evolved as they usually do, so now I am adding some indexes so you can jump right to the section that interests you"
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JACKING THE BATTERY with a motorcycle lift.
DROPPING THE BATTERY with a truck innertube.
THE HV BATTERY CABLE connections.
HORIZONTAL RAMPS for moving the car over the battery.
BAD MLEC BOARD in my THINK BRICK.
BAD MLEC in my THINK PITT.
THE TRAVELING DIAGNOSTICS KIT
Adding a REGEN or FAST button to the shifter.
Adding cupholders.
Adding an LED dome light.
Adding a protective fuse in the L1 EVSE.
Adding a side visor.
Adding an easy-access 12v battery.
Adding a coffee-pot Timer.
See my other non-think EV projects.
After a little cleaning with alcohol and flipping the board around the other way,
it appears that the conformal coating protected almost all of the chips though,
some of their contacts may have been contacted by the 400v plazma. Which one would
assume would blow every component connected to those exposed leads.
Also notice crinkled paint, bare metal and evidence of violent activity on the metal plate
off the edge of the board. I cannot conclude that there was an arc-over-to- ground, but similarly,
I cannot rule it out.
The OEM resistor is labeled: HVR APC U 2115A470K 101.V. It is a surge rated 47 ohm resistor,
rated at 3.5W and 700J surge. Here is the Manufacturer's link.
They cost about $6, but Minimum order is $50.
UPDATE: Bad news probably... Despite the total apparent destruction of the resistor I just measured it
and it is 53 ohms... pretty darn close to the original 47 ohms. This means the arc did not quench here.
Also the PCB traces are good to the white connector (2 pins closest to the resistor) and the resistance
from either of these pins to ground is greater than 50 meghoms.
So MLEC board and resistor may be good.. something elsewhere may be my problem?
New Resistor on order ($50 minimum, so I bought a few spares).
REPAIR: I put the new resistor on the board and
as a precaution, covered the area surrounding the
resistor with a few layers of high-temperature
Kapton tape (used extensively in Aerospace) as
shown in the image here. This way if there was
another resistor burnout and 400v Flash arc, it
would not reach the delicate electronic components.
BAD NEWS: With excitement I crawled under the car
and reconnected the repaired MLEC board to the
Battery very carefully reconecting all the
connectors (and checking the two hidden blade fuses
in the wiring harness along the lower edge.
Crawled back out and tepidly turned the car to start
.... Nothing...:-( but I did get a new indication...
the Yellow Fuel Pump looking light lit.
GOOD NEWS: Duh, I had forgotten to reconnect the
battery pack! Crawled back under the car and
plugged in the battery interface cable and large
orange battery connector. As a precaution, I
unplugged the orange HV heater plug from the PCU
under the hood and the three pin black connector
near it to make sure the heater could not cause any
problems. Crawled back out and tried again...
BAD NEWS: Still nothing. Gave up. Coverd the BRICK
with a tarp and left the car for several days.
GOOD NEWS: 9 April 2015, on a nice clean fresh sunny day, had a thought. What if the HV heater
connection is somehow interlocked and the PCU simply does not like being left exposed
with an empty connector.. Plugged in the orange plug, jumped inside and for the first
time, heard the PCU startup on "start" and going to D (drive) and the jacked-up wheels
started turning! I got a new EV! Happy end of story.
BAD NEWS! Bought decals all over the car promoting EV's. Registered it, drove it about a month
but it went from about one shut-down fault per week, to one a day, to one per trip to one before
even leaving the neighborhood. Then it would not charge, so it was abandoned again as yard Art
for a year...
JACKING HTE BATTERY WITH A MOTORCYCLE LIFT:
Oh, lessons learned on getting the MLEC board out. First, you have to be able to
get the car up at least a foot higher than the lowest point that you can lower the
battery. I used the 1500 lb motorcycle jack from Harbor Freight shown here for the
battery and a regular hydraulic jack around-&around&around the car for the frame.
This lift purports to be a parallel lift, but most of the lifting is on the rear arms
with about a 1 inch droop at the front under load at low levels, so I centered the
lift a bit forward of the battery center and used crossed lumber to spread out the
load (losing more clearance). View below is from the front looking back with battery
down about 6 inches.
That combined with 4 jack stands, 4 cinderblocks, several scraps of 2x10 and 4x4
posts and 2x4's and multiple-multiple jackings and re-configuring finally got to
where I got the battery down about a foot and the car WAY up there so I could remove
the MLEC board in place. You can see the panel on the right side of the front of
the battery where the MLEC panel is removed and the ribbon cable hanging out.
The panel (with MLEC attached on its backside) was not trivial to get out since it has
edge connectors on both top and bottom edges of the board, neither of which will fit
through the hole in the side of the battery box at the same time. SO you have to very
carefully try to remove the bottom edge connectors with your fat fingers in a tiny space
(while pressing the release button on each).
Be careful removing the board and connectors as there could still possibly be 400 VDC on
the white connector if one of the HV contactors had failed and there was another ground
fault somewhere. Take care not to touch a pin or rub through the wire with all the
josstling on the edge of the metal frame.
The image above shows how the lips of the battery are resting on the four cinder
blocks to remove the load from the lift while the THINK brick awates its fate.
That's it for tonight. Friday 13 Mar 2015. Now to find a replacement part!
------------------- and that was it for about 6 months... --------------------------------------
GOOD NEWS (or not) JULY 2015: I bought another THINK for parts. I named this one the
THINK-PIT since it came from Pittsburg. Talk about doubling down on a dumb investment. But
from the time I looked at it in May to when I bought it in July, to when it was finally
delivered in December, even the THINK dealer in Indiana has now liguidated so there is zero
support anywhere.
INNER TUBE JACKING: So this time I decided I would try an easier method of getting at the
battery by jacking it down with a truck innertube. Turns out the tubes are only about $16 new
from any tire place (though special order, unless it is a truck tire place). The only one
he had in stock was not the most common tube, but it turns out it was perfect. It is about
36" in diameter deflated. See here how I used a tire inflator to raise the car about 2" to
off-weight the battery:
I first removed every other battery bolt and all of the ones on the front and back. Then got to
only 4 (each supporting 200 lbs), one bolt in from each corner. Then ran the pump until the car
and battery were raised about 2" where the tube was supporting 100% of the battery weight. Then
I removed the final four bolts.
PLAN AHEAD! Of course, I had given no thought as to how I was going to lower the pressure in the
tube and had to take apart the compressor so I could poke a stick into the valve of the compressor
to let the air out! This worked well, actually, but seems kludgy. So I simply let the air out
and the battery began to descend. There was a mad scramble at the end when I realized the 700 lb
battey would crush the tube's air valve and inflator clamp when all the air was gone. SO I slipped
four blocks of 2x4 scrap under the corners of the battery to keep it a final 1.5" off the deck.
For my next use, I bought a small brass "T" and inserted it in the compressor hose. When I want to lower
the car, I just remove the plug in the side of the "T".
Once the battery is on the ground, then I had to begin jacking up the front end of the car so I
could get under it and disconnect the battery cables. Turns out, I had to raise the front end
over 7 inches in order for the car to clear the battery. I did this with raised wood ramps so
that I could actually move the car backwards to reveal the battery before doing any work on it.
This is not necessary to get to the MLEC board, but I figured I'd do it anyway. So the 7" ramps
were level going back at least 6 feet so I could push the car on "level" surface. The final
picture below shows the battery revealed. What a monster.
The ramps shown here are not the improved ones I eventualy used for my third battery drop as
detailed further below.
My FINAL RAMPS for Moving the Car over the Battery:
To move the car back and forth over the battery for repairs, and re-testing (my third time), I made
a set of level ramps to keep the front wheels 7 inches off the ground. The seven inches is necessary
to clear the battery but only if the rear is also up by 1.5 inches. You could go higher on the front
and eliminate the back 1.5 inches but then it was too high for my hand jack to lift in one swoop.
You need two sets of these, one set for each side. Plus you need the added 2' one that I never photographed.
Again, at the time of this battery repair, I had not built the 2' initial front ramps and just jerryrigged
from lumber laying around. That is when I noted that making a 2' section for the initial jacking of the front
allowed you to get to the battery along the sides for unbolting, before starting to use the 4' sections to
back up the car and reveal the battery for opening and repair.
The above photo shows the lifted car moved back on the ramps to clear the battery for repair. But, come to
think about it, the shorter 2' sections would not be needed if the initial jacking placed the front wheels
on the back end of a pair of 4' sections. Then you could end-over-end the 4' sections to do the same thing.
The down side of this is having to lie on the ground between the two 4' sections sticking out the front while
you do all your initial jacking. I think I would still build the two 2' sections to avoid those gyrations.
AND IT IS ANOTHER BAD MLEC:
And of course, when the MLEC board was removed, not only was the pre-charge resistor smoked, but
you can also see the arc got into the Ribbon cable rubber. This does not look good.
At this point, I have not jacked the battery back up with the compressor, or reinstalled the battery,
but I do not anticipate any significant problems other than getting the car, on ramps, aligned so
I can then jack the car back down over the battery, and then when all is aligned, jacking up the
battery and bolting in place.
JULY 2016: That was 6 months ago. I finally repaired the MLEC board. Reconnected everything and
the car works! But it took a long time to get the title and bill of sale) and so now a year later
(July 2016) it is finally on the road (though the local garage has still not given me my final
safety inspection document to make it fully legal. He says the side yellow light is a clearance
light and is not working. He would not accept the picture in the manual that says it is a turn signal
(that works). The inspector was an arrogant gasket head and after 2 weeks of arguing he finally signed
the safety inspection and said "dont ever bring me any EV's again" to which I responded, "I certainly
won't!". He had, over the years also inspected three of my salvage Prius restores, a Honda Civic
conversion and two THINKS. Now I will go across the street to the cheap gas station and save 10 cents
a gallon too!.
THE TRAVELING THINK DIAGNOSTICS KIT: In later July, I received John Mayer's "traveling THINK
diagnostics kit. For $150 a week, it is a great service to be able to finally see what was wrong
with the THINK BRICK. Frank Smith, who also has a workign THINK in my neighborhood worked with me
to plug in the kit's THINK PC interface and read diagnostic codes. We found that an RLEC was not
reporting any data. John shipped us a new RLEC pre-programmed with the ID code of the bad RLEC and
when we installed it, the battery worked! SO now for the first time in a year, the THINK BRICK was
not giving any codes on the CAN bus and not giving any error lights on the dash board.
The relay's did their dance, the PCU starts up and hums... But putting it in gear, and the motor just
will not run. Nothing. John and all of us are out of ideas (other than replacing the PCU for $3000.
So now the THINK BRICK has re-earned its name and is again a nice colored yard ornament. But at least
its battery is now installed and attached so I can move it around the driveway instead of being
permanelty ensconced over the battery on the ground.
While it was down, I just updated the firmware using John Meyer's portable laptop and now I
have that EV acceleration grin again!
CUPHOLDERS
I got so fed up with trying to get a drink into and out of the THINK cup holders as it would fold up on me.
So today, I realized the simple fix. Take a large plastic drink cup that fills the cup holder, rinse and then
insert it all the way down into the holder. Mark a circle on the cup around the top of the cup holder.
Remove the cup and cut about 1/4" below the line all the way around. Then insert this "short cup" FROM BELOW
so that it is held from going up by the top part of the cup holder and from going down by the base of the cup
holder. You now have a solid cup holder into which you can insert and take out paper and plastic cups without
it collapsing on you. My cup was a see-through clear one from 7/11 so it is not obnoxiously visible when not in use.
Also note the black 3/4" angle bracket inserted under the plastic seat slide cover that keeps the breakfast
cereal cup in place. Just slip the bracket under the plastic on both sides, and now my breakfest cereal cup
does not go flying when I have a panic stop in the morning.
MY LED DOME LIGHT
I got tired of runing the battery down when I left the dome light on. So I replaced the bulb with
a homemade LED lamp. Although you can buy these LED lignts now stock from any auto parts store,
I had all the LED's so I made one. In the photo it is crooked because I made it too long by about 1/16"
and I have only made one so far (need another roundtoit).
I used three series strings of 4 LED's in parallel. Then the entire set was then series-ed with a small
Xmas tree lightbulb. The lighbulb acts as a constant current source with a little voltage drop to keep
the current from being too high when the battery is at 13.8v. It would have been a better match to the
Xmas tree bulb if I had used four strings of 4 LED's in parallel. But they would not fit on the board
I had pre-cut, so I replaced the 4th string with a resistor to better limit the current to the other three
strings to the desired 15 mA per string.
PROTECTIVE 15A FUSES IN THE EVSE
A lot has been said about the 9 hour labor involved in removing the PCU just to replace a blown 20
amp internal fuse and put it back in again. For those of us that use the same L1 EVSE at home or
take it with us to charge, a nice place to put an external 15 amp fuse is inside the original EVSE
where it even has traces for a fuse on both sides of the line. Just carefully remove the #12 wire
jumper and somehow solder your fuse in place. I heated one end of the #12 wire (so it could move
to relieve stress) and then cut it in half with dikes. Then while heating each end, bent the #12
ends up so then I could solder the fuse to the wires as shown. Easier to replace these 15A fuses
in the EVSE than the 20A inside the PCU that takes a day of labor.
SIDE VISOR:
With the high window glass compared to other cars, I find the morning and evening sun beams in the driver's window
into my eyes. Yet the visor in the THINK is not long enough to swing over and block the sun. So I made this
simple shade out of a piece of cardboard and just slide it up into the crack in the door whenever needed. It just
slides in easily (though it will fall out when you open the door).
EASY-ACCESS 12V BATTERY
After taking out a bad 12 volt battery, there was no way I was going to put another one back in.
What a nighmare of contortions for such an important thing as the 12v battery. As a Ham, I run
all kinds of things on 12 volts and so need separate access for both use and charging. So here,
I put a small 7 AH gel cell in the glove tray and connected it to the fuses there. A small block
of wood screwed from the bottom to the plastic fuse cover holds the battey from sliding. To
wire it up, I soldered a wire from the + terminal to the top end of one of the 30A fuses as shown
in this Fuse mod-pigtail photo (but make it longer than shown there!).
Of course, this battery will run down in 2 days due to the 30 mA of idle current drawn even when the
THINK is turned off. So I backup the battery with a small solar panel on the roof with its own small
13.8v charge regulator. It is easy to drill from the outside, install the solar panel and then run
the wires over to the corner pilar and down to the battery. The pilar cover should pop off, but mine
did not, and tore off both snap on connectors. Duct tape restored it.
I had taken some pictures of my original "just-get-er-going" approach. But that was before I cleaned
it up as shown above. first battery, closer view.
COFFEE MAKER TIMER:
My commute only uses about 30 to 40% of battery range and can be replenished from about midnight until
I leave in the morning. Not wanting to have to remember to go out and plug in every night at bed time,
I found this old Mr. Coffee control panel. You can set the time to any start time you want and the
charge will begin at that time. The timer contains a 12 amp relay for the coffeepot, but I figured
that was not designed for many hours of continuous service so I mounted a heavier duty relay in a box
on the back of the garage door. Then on the front of the door is the timer at a nice easy height for
setting the time, and the outlet down at a plugging-in level. The coffeepot ON/AUTO/OFF switch also
controls the relay for any other selection I want too.
It is not weather proof, so normally the timer is coverd
with a clear plastic cutout from a plastic bottle to keep
it dry of falling rain.
Bob, WB4APR
Back to Top
REGEN BUTTON: This is my first hack to the car to add a REGEN button. It lets you
Drive in D and to slow down with maximum Re-Gen in E by pressing a button on
the back of the shifter. Looking at the table for all the conditions of the microswitches
on the shift lever, one can see that both the A and C switches have to change state in
going from D to E. But this can be accomplished with a single SPDT switch as shown.
The new "Regen Button" is shown in its rest state. In this condition, it maintains
the normal ground connection on the bottom of switch A for normal operation. It is
also then Open to the top of the C switch. Thus, the switch is transparent to normal
operation. But when the Shift Lever is in D, and this Button is pressed, it
simultaneously opens the A circuit and closes to common the C circuit.
So, I mounted a microswitch from an old mouse on the front of the Shift column with
black tape so that I can simply press it when I want max regen. An analysis of what
happens if I accidentally push it in any of the other gears reveals that in both
Reverse and Neutral, the switch states will appear to be the same as the normal Park,
except that the D switch is in an invalid state (and hopefully ignored).
Similarly, in the DRIVE position, the button has the desired effect and when in the
ECO position, the switch has no effect since the switches are alredy in that state.
In the PARK position pressing the button should give an invalid code and someone has claimed
that this will throw a fault and rquire you to re-start the car. But I have not seen this.
(and I cannot be sure I actually tested this state, since this car ony ran a month before it
had MLEC and RLEC problems plus NO-GO terminal problem. Caveat Emptor.
So this is a nice HACK for easy driving in D and dropping to E with the press of this
convenient button for slowing down.
UPDATE 2016. CHANGED TO A FAST BUTTON: Now with my second THINK, I have decided to
reverse the connections to the added microswitch so that the button is no longer a
REGEN Enhancer while in DRIVE, but now it is a DRIVE Enhancer while in ECO mode.
I like this much better since you never know when you might need to brake suddenly,
so I prefer to always drive in ECO mode to make sure that I always get MAX REGEN
at any time to minimize brake wear. With the button now wired for FAST, now I can
drive in ECO all the time, but when I need a quick boost (as in DRIVE), all I have
to do is push the (now lableled) FAST button. Notice the wire cuts and taps now
move to the other switch in the shifter so you have to take it all apart again to
make this change.
Notice the switch positions and logic table are very confusing. There is lots of
reversed and double reverse logic. IE, a 1 is a ground, and the definitions of
PUSHED or RELEASED only translate to a TRUE or NOT TRUE depending on which switch
contact (NC or NO) is actually wired. So look carefully at the truth table where
I added the NC and NO on each switch to show how it is wired.
Shifter Switch Photos:
Mouse switch,
Switch Prep,
Placement,
Switch view,
First Screw,
ABC switches,
Wiring,
I had considered to wire up the added REGEN button to a relay connected to the brakelights
to save me the trouble of pushing a button during panic stops. But I don't like having to
move my foot to feather the brake pedal to get the extra REGEN when i touch of the finger
is easier to do. Plus, all that added wiring (most of it snaking wires all over the car),
makes that job a whole lot more time-cousuming... which means I probably will never find a
round-.
MANUAL METHOD: Instead of doing all the above, someone on the THINK yahoo group suggested
using one's hand on the emergency brake and then using the thumb to slip the shifter easily from E
back to drive. This works very well. But I fear it adds a lot of wear and tear on the shifter
microswitches and since them becoming loose is a known difficulty with the car, I prefer my added
button so I only shift once when I leave and then back to Park when I stop.
Bob, WB4APR
THINK #1, now named THINK-BRICK:
This think was bought at GSA auction for $3700 and not working in Jan 2014. The other four
at the same auction drove across the auction line and went for over $7000. I gambled because
the THINK had clearly been driven to the auction by GSA but probably someone during "open viewing"
cycled the key the wrong way, and it died. (or maybe it was towed there?)
BLOWN MLEC BOARD:
The incorrect cycling of the key switch can BRICK any THINK if the heater was
left on on the previous key cycle. This causes the full heater load through
the Pre-Charge resistor and it has to dissipate 3400 Watts instead of 5 Watts
with resuluts as shown here. This is a common failure of the THINK which was
supposed to have been corrected via a software upgrade to make sure the Heater
was off even if the dashboard switch was left on. But even with this software
protection, the failure can still occur due to the small time delay between when
the control is removed from the HV heater circuitry and when it actually drops out.
SO, if the key is rapidly turned from ON to OFF and back to ON again, positions 0 and II
and if the heater was on, then despite the software protection, the HV heater is still
connected during the many milliseconds that it takes to cook the resistor. Notice
this vulnerable period is simply going to ON (II) when all the contactors are doing their
thing and not actually going to START (III) as was previously thought.