VEC300 problem determination, any help appreciated!

[Evolknuj]

I actually attached this to the bottom of my Cyclekart 3-wheeler post already, but just in case that wasn't seen I wanted to start a separate thread.  Apologies for the "double post" essentially, please feel free to slap my hand and delete this if it's a severe etiquette breach.

The problem:
Dangit.  Last weekend after taking a spin around the driveway I cleaned up the mess of saw dust and metal shavings in the garage.... and the 3-wheeler wouldn't start.  Multimeter verified voltage was available at the controller, but no reassuring "beeeep" of it turning on at all.  It had worked just fine 10 minutes prior, and hadn't been doing anything strenuous.  I tried it again a day later and still dead.  My son tried it a couple times and claimed it beeped once... but now doesnt.

How can I debug what's wrong?  I have the USB cable, but have never used it before -- is there a good guide to how to do diagnostics?  I'm not even sure where to get the software I found the software but I'm not sure if it only needs the USB cable hooked up or also needs to be connected to battery for diagnostics.

Any help appreciated!

Edit: Even basic help!  E.g. I have the controller inside with the battery to try to diagnose now.  Do I need to have it hooked to the motor for the controller to come on and/or do USB diagnostics?  Or should it come on and beep and light up in isolation?  Can't remember if I even tried powering it without the motor connected when I originally got it.

[Bikemad]

Hi Paul,

As the controller was obviously working OK when you took a spin around the driveway, could the battery voltage have simply dropped too low while you were sweeping out the garage?

I found the software but I'm not sure if it only needs the USB cable hooked up or also needs to be connected to battery for diagnostics.

I suspect that battery voltage will be required to enable the controller to connect and communicate properly with the software.

Faults are usually determined by the number of regular blinks coming from the controller's LED. (Details of the blink codes can be found on page 5 of the VEC Controller guide).

First, ensure that the controller is properly grounded via the B- connection and then check that you have suitable battery voltage on both sides of the fuse.
If you only have battery voltage on the B+ end of the fuse, the fuse will either be blown or possibly have a very poor connection onto the terminals.

Next you will need to make sure that you also have full battery voltage reaching pin 10 of the 30 pin connector to confirm that the e-lock switch (and its associated wiring) is working as it should.

If there are still no beeps (or blinks coming from LED) I suspect there will be a problem within the controller itself, which should be covered by the warranty. 

Alan
 

[Evolknuj]

Thanks Alan.  Unfortunately, there are currently no flashes or beeps when the battery is connected.  The fuse isn't blown.  I will double-check the pin 10 of the 30 pin connector and the e-lock.  Should the controller only light up / beep if the e-lock is on/connected?  Or should it light up / beep, just not power the motor, when the e-lock is disconnected?

[Bikemad]

Unfortunately, I've never personally used (or even seen) a VEC controller, so I don't know what the typical power up indication is. 

Perhaps someone else with a VEC controller will be able to say what happens (regarding the audible beeps and visual LED flashes etc.) when you connect the battery and also what happens when the e-lock switch is subsequently turned on.

If the controller is powered up while it is disconnected from the motor, I would expect to see a continuous error code being indicated by the blinking LED, but I'm not sure about the audible beeps.

Alan
 

[Evolknuj]

Solved!  This was the key (pun intended as you'll soon see:

confirm that the e-lock switch (and its associated wiring) is working as it should

I confirmed that my e-lock pins did have voltage -- full battery voltage to my surprise.  I was expecting them to have 5v like the brake and throttle pins.  So I stuck a paperclip in as a quick and dirty switch and it beeped and lit up.  Reinstalled everything in the car.... and nothing.  Apparently the length of wire and the key switch I am using for the e-lock either can't handle the voltage or introduce enough resistance that the controller does not recognize that it's closed.  Even though a multimeter shows there's essentially zero resistance when the key is turned.  Replace the paperclip and the car runs like a top again.  Maybe it's just the connector to the elock pins or something, but it's not the controller itself.  WHEW!

Thanks so much Alan for the tips -- they put me on the right track to diagnose the problem!!!!

[Bikemad]

I confirmed that my e-lock pins did have voltage -- full battery voltage to my surprise.  I was expecting them to have 5v like the brake and throttle pins.

It should not really have been a surprise, as "full battery voltage" is what I specifically said you should check for:

Next you will need to make sure that you also have full battery voltage reaching pin 10 of the 30 pin connector to confirm that the e-lock switch (and its associated wiring) is working as it should

And the wiring diagram clearly shows that one side of the switch is connected to B+:


Anyway, it's good to know that the problem has been found. 

Alan