Mazda MX-6 build thread (EV conversion)

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Originally Posted by Astro

I have never used these controllers before so the following is just a guess.
I would say the controller giving an error when the throttle is below a few percent could be correct behaviour.

I think the controller is acting as programmed. Perhaps the throttle is off by a bit. The issue appears to be B channel below 0.20 V

When you put the throttle control in the car the pedal would hold the throttle at something above zero with foot off.

I tried setting the throttle to above 0% (future video). The controller allows the start, but wants the throttle back down to 0% before it will drive the car. So I have the throttle at just below 0% and I can adjust the pedal position when starting. This works but is less than ideal.

I may try to re-calibrate with the throttle starting at 1% or so. That may work?

I would imagine there would be a high pedal lockout as well which would bring up an error at 100% throttle control travel. Full throttle from the pedal (foot flat to the floor) would likely only give 95% of throttle control travel. Anything higher would be recognised as a possible return spring break and present an error.

There is a high throttle lockout. The condition you describe could trigger it. The A channel is also about double the value of the B channel, so if the channels do not agree, the throttle faults as well (like if a wire is not connected because I didn't have the connector all the way in. B channel was at 0.00V)

I imagine that is why there is a calibration sequence so the controller can find where the zero pedal travel and full pedal travel appear in the available throttle control travel.

There are only a couple of throttles supported. I expect that the calibration may be to support other throttles. But that's a guess on my part

When my Min-SD card arrives (not micro ... there is a spec for Mini SD that was popular for about 10 minutes). This is the memory card that the Controller supports for logging and for upgrades to the firmware. I expect that the firmware is *WAY* behind.

[thingstodo]

Preparing battery pack to go into car

Weigh 1/3 of battery pack

Sling the battery pack

Mazda MX6 Day 113 Video 034 Oct 20 2014 - YouTube

Battery pack install inside car continued

Weigh last pack on the way in

Mazda MX6 Day 113 Video 034 2 Oct 20 2014 - YouTube

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Talk about cables exiting the car

Bracing the battery box inside the car

Mounting the controller under the hood

Mounting 2 batteries (for now)

Circulating cooling fluid through radiator and controller

Mazda MX6 Day 115 Video 035 Oct 22 2014 - YouTube

[thingstodo]

I took the day off my day job and worked on the car. It's a nice day and we won't get many days warm enough to work on the car outside!

Not much progress for a whole DAY!!

- mounted the fuses behind the driver's and passenger's seats in the car, with upcycled cottage cheese containers for plastic covers

- mounted the disconnect switch, shunt, and positive tie point at the rear of the batteries, front of the trunk

- drilled holes in the floor and ran the two temporary power cables from the battery pack to the front of the car. Fabricated/bent up some cable supports so the cables do not drag on the ground.

- make the L brackets and OSB mount for the controller - not installed yet

- wire up a DC breaker for the front engine bay. I can't find the trip cable that I bought with it, so it's just a breaker for now, and it's big. The Gigavac contactors won't fit inside the box. So it's too big to fit with everything else ... I guess I'll skip that one for now.

- mount the accelerator potbox/hall effect replacement and connect to the existing throttle pedal. Not tested as yet, but the cable moves back and forth.

I didn't take video but I guess I can take some pictures (a few days late). I will post tomorrow with the next update

[thingstodo]

I spent the day fabricating mounts for
- fuses at the rear of the car (L brackets on insulators),
- fuse in the rear of the car (inline fuse with fuse cover),
- the manual disconnect switch plate to the car,
- shunt (remounted on the shunts on insulators)

Put 24V of battery into trunk and test run controller

There is no control from inside car. RUN and START signals are jumper wires with alligator clips under the hood

Results:
- accelerator works
- I can shift gears works without the clutch - at least while up on jacks
- the rubbing on the motor slows down the motor between shifts, almost to a stop

Run a cable from the engine bay to inside the cabin for rj45, so the Interface Module will work where I can see it

Run 1 pair of wires to display the engine trouble light

Again no video and no pictures. And I didn't get pictures of the Oct 23 work as yet. Perhaps tomorrow?

[thingstodo]

A regular SD card does not fit into the SD slot in the Interface Module.

That's where you add memory so that the Interface Module can log exceptions, log motor voltage and current, battery voltage and current, log information should there be a failure to aid in troubleshooting ...

It is a Mini SD not a Micro SD. No longer sold by any vendor locally ... but I need one that is 2GB max, formatted FAT. Ebay will take a couple of weeks ...

And I need access to the transmission to top up the transmission oil, check the speedometer cable

To do that, I need to remove the controller, disconnect the motor cables, move the contactor mounts and the controller cable breakout out of the way.

Then remove the speedometer cable and examine to see if it is broken or simply not engaged

If broken, see if parts can be sourced. If disengaged, figure out how to engage.

If it was engaged, try running the car with the ignition on in case that is all that was required to display the speed?

Further to my quest of starting the controller from inside the cabin of the car (via the key switch on the steering column) - the starter cable (the cable that connects to the old ICE starter) is connected to the battery all of the time. That cable is not switched by the ignition

A relay connects the negative of the starter to ground on the battery. Mazda 626GD MX-6 1990-1992 Wiring Diagram.pdf, page 50-16, D-02 .. plus the the (!@#$!&^%) CLUTCH MUST BE PRESSED TO START THE CAR!!!

You'd think that the clutch would be sorta obvious, pressing it to start up the car would be something that you do without thinking about it - EVERY TIME you get in the car. Well, since I DON'T think about it, I didn't remember to do it when I was listening for the 'click' of the relay during a start from the ignition switch... sigh!

- having some trouble with my phone. I will get pictures posted as soon as I get it figured out -

[thingstodo]

OK - I got the order for the Micro SD card (1 GB) and Micro to Mini SD card adapter for $8.50 US from china done. I gave up trying to find a local source that would have it here faster. But it will be 3 weeks before it arrives ...

So I should concentrate on getting everything to support the controller in and working before the MicroSD card arrives. I'm waiting on the MicroSD, so it should not sit in it's package, waiting for me to get stuff done once it arrives. I should try out the data logging, updating the firmware on the controllers, etc the day it arrives.

First step, power up the car with 12V on the controller, a 12V starter battery for the car (since there is no DC/DC yet), and a couple 12V deep cycle batteries as a 24V High Voltage (or higher than 12V) pack.

Begin by turning on the controller from under the hood. I'm using 2 alligator clips

Now turn on the rest of the car - press clutch, turn key. I hear the click of a starting relay - good news!

Press the accelerator. The Motor turns as it should. Release the accelerator and let it coast down.

Put the transmission in 5th gear and repeat. The backlight is on for the dash. The speedometer still does not work. That's a bit disappointing - I was hoping that putting the starter battery into the car would enable the display of the speed. Kinda silly.

Back under the hood. Add the RJ45 female to female adapter to the RJ45 cable on the controller. The other end of the second RJ45 is run through the firewall and inside the car. Sit the Interface Module on the passenger's seat. It works! Try the accelerator again and watch the pack voltage change, the motor voltage change, and the currents.

Shut everything down. Remove the 24V pack from the trunk. I made a conscious decision NOT to check the controller with the 400V pack. The connections are awkward, the time is late, and I will likely make a mistake.

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Remove the shroud from the motor. That's the part that is rubbing on the axle as it rotates.

Move inside the car. Interface module is inside now.

Run the motor up in neutral (100A is too low, even for neutral!)

Duplicate the test with 300a maximum on the motor. It runs fine

Put the car in 3rd gear, then run up the car. I didn't check the speedometer

Mazda MX6 Day 125 Video 036 Nov 1 2014 - YouTube

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Late decision to do first run today - 4:30 pm. I've got about an hour of light left.

Locate the start relay for the car on the electrical diagrams. It is beside the starting battery, beneath the fuse box.

The RUN relay is much more difficult for me to find. The wiring diagrams show an Ig1 relay, on with car in ON position and does not drop when START is energized. It is in JB-07 ... but I can't figure out where JB-07 is.

Use a single pair of wires, that were run from inside the cabin of the car to the engine bay to drive the check engine light, as an interlock. Wire the 12V 'ON' signal through that pair of wires so I can shut off the controller from inside the car.

Drop the car off the ramps and the jacks. It's sitting on the ground for the first time in many weeks.

Power up the controller on the full pack - 384V - like in the last video. All appears to work fine.

Reverse the car (using the reverse gear, of course). The car sounds HORRID! There is a gravelly sound!

The supports for the battery pack (remember the 2 x 4s?) are DRAGGING ON THE GROUND. This is the first time I've had the car off the ramps, so I never knew that the 2 x 4s were too long and had no clearance with the ground below the car!

I crawl partially under the car (it's not up on jacks, so I don't fit under the car) and use a sawzall to remove the excess length of 2 x 4s that were too long (all 8 vertical supports). The cuts are awkward, not straight, and I bent the crap out of my blade ... but they got cut.

And we (Andrew and I) take the first run down the driveway. No video - we were in a hurry since it was getting dark.

First trip down the driveway, battery current limit set to 300A, motor voltage set to 160V and motor current limit set to 300A. These are the settings that I ended up with after the last video. 1st gear felt OK but there was a *LOT* of road noise. Kinda like the supports were still dragging.

I tried a shift to 2nd gear without a clutch ... it took a couple of seconds but it worked ... and we were accelerating again. AGAIN, it sounded like the battery supports were STILL dragging on the ground. The speedometer works .. this was a surprise. I have changed NOTHING.

I was up to 40 kph before I hit the end of my driveway. (My driveway is 550 feet long - about one tenth of a mile). I didn't identify the noise.

Turn around and drive back to the starting point a bit more slowly. There is much less noise?

Second trip down the driveway. Leave the battery current limit at 300A, motor voltage at 160V, but crank up the motor current limit to 1000A! It's insane for the second run, but I want to know if I could pull those kind of amps. The car is put in 3rd gear - that should pull more amps. It still sounds like the battery supports are dragging.

I get to the end of the driveway (Andrew was reading off currents as we went, but I don't remember them). I didn't see the max speed, either.
BUT, we hit overtemp on the controller, near the end of the driveway ... since I DON'T HAVE ANY LIQUID COOLING CONNECTED!!! I thought I would not reach overtemp with the weather at 40F ... but I did. I guess the second run, plus the larger motor current ... well, I guess I was asking for it!

We didn't really know the controller hit overtemp. The car just died. We began coasting and I hit the brakes before we got onto the local gravel road.

I pushed the throttle to turn around and nothing happened. I reset the throttle, checked the controller faults ... so we looked at the interface module display. The controller temp was 54C. I'm not sure how high it got.

After a few seconds, the controller temp dropped to 40C but I think that my throttle was still at some percentage and we experienced a bit of a 'surge'. We were pushed back into our seats briefly (spinning tires). I heard a 'pop' behind me. Sounded like a contactor, but louder. But the contactors are under the hood. Behind me are two isolation switches and 3 fuses, along with the battery pack.

After dragging the car back to the garage, for some tools to do some troubleshooting, I found no high voltage to the controller contactors. Working my way back through the isolation switches and fuses, I found at least ONE 300A fuse had blown. It is there for short-circuit protection. It should not have tripped under 2000A, at all, and I don't think my pack will put out 2000A. I had a sinking feeling ...

Andrew looked at the driveway and figured out that the noise that we heard, that sounded like the supports were still dragging ... was the FRONT TIRES SPINNING ALL THE WAY DOWN THE DRIVEWAY. I had dug grooves in my gravel driveway! You'd think that I'd have noticed the grooves in the driveway when we were driving back to the house, or dragging the car back to house to do troubleshooting.

So I THINK the clutch, old as it is, will hold for enough torque to get me into trouble.

Next time
- figure out if there is a ground fault somewhere
- replace the fuse
- power up the controller and see if anything else is broken

[thingstodo]

The fuse was successfully replaced. Only one fuse was blown. The one behind the driver's seat.

The controller still does not work. The 'sound' of the contactors has changed. The error codes have not changed - 16 and 17.

So I checked voltage. After the controller faults, there is 380V from + to - on the pack side of the two contactors up front. So far so good.

Check voltage across the positive contactor. It's 0V? Voltage is all across the negative contactor - it's 380V? It appears that the positive contactor may have failed in the ON position?

That is consistent with blowing the fuse. The 350A fuse actually blows at upwards of 3000 amps in a time of 10 ms. As the current drops (not very much, either) the time to blow the fuse increases. It may have taken 500 ms to blow the fuse - we got acceleration during that 'surge'.

I did not, and do not, EVER expect these fuses to blow unless something has gone VERY VERY wrong. If the Gigavac contactor has welded the contacts, there was definitely a large current flowing when it tried to open.

I guess I need to order some parts from EVTV. 2 Gigavacs to replace these, and 2 more for the WIKISPEED car. I will likely hold off on the DC/DC converters, the orange conduit to hold my #00 cables, etc until I need them.

While I'm waiting for the parts to arrive, I may try to replace the positive gigavac with a Chinese reversing contactor that I had purchased last year for another project. If that does not get the car running again, I'll wait for the parts to arrive.