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Discussion Starter #1
I have a Tesla 80A wall connector that is dead. When connected, it does absolutely nothing - no lights, sounds or anything. It is not eligible for a warranty replacement...long story..., so I cannot just send it back as, it appears, everyone does if they have a problem. I have opened it up and inspected, verified 240 volts is getting to the contactor terminals inside and I can't see any damage or a fuse. Before I start troubleshooting blindly, does anyone have any suggestions or a schematic that would help me decide where to look? The circuit boards are coated for moisture protection - good for reliability, but a lot more trouble to probe.
It is less than 1 year old.
If I understand correctly, it's function is to control the 240 V power going to the plug. In it's simplest form, this would be a switch and an extension cord, but in the real world it has safety interlocks, settable current limiting and interfaces with the car to determine when to turn on and shut off.
 

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It sounds like you have lost the low voltage power supply.

if you could post up a picture of the inside maybe we could help. i have reversed the circuits of the panasonic units and also looked at the early tesla model for which i think someone on their forum has schematics.

Seems like they all have a fuse on the supply for the low voltage control power, but it may be covered with the black goo on the logic board. Hopefully it is not hard epoxy--the rubbery type can be easily removed with a bamboo chopstick whittled to a flat blade or a pointy tip as needed to scrape it.
 

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Discussion Starter #4
Thanks for the suggestions!
I tried to take the circuit board out to better see where wires go but it will not come out due to the little clear-and-silver strip on the lower right. It goes into a hole in the case and I can't see a way to unplug it. Might go to an LED? or to provide evidence of tinkering?
The parts on the lower left look like an AC to DC converter but nothing is labelled.
 

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I tried to take the circuit board out to better see where wires go but it will not come out due to the little clear-and-silver strip on the lower right. It goes into a hole in the case and I can't see a way to unplug it. Might go to an LED? or to provide evidence of tinkering?
That just looks like a two-conductor thin ribbon cable. I would guess that it runs an LED or is connected to a switch.
 

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The two white boxes at the left are the main contactors which switch ON to provide AC to the car. But i can't read anything in the picture on the right.
Take another picture showing the entire interior without shadows, and in the normal orientation where the top of the unit is toward the upper edge of the picture. Does AC from the mains come in at the bottom, or is there some plug on the back? It's not clear where the mains gets attached inside here. Also is the handle wiring already connected--where does it attach, is there a terminal strip?

It looks like the AC is brought in to the board and rectified with diodes on the board, but it's too dark a picture to read for sure.
 

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Discussion Starter #7
I found out the little wire was just glued down, so I got the circuit board out. There are cooked parts on the underside, sort of visible in the pictures, upper left (directly under the DC power supply parts).
I don't know if it is possible to get replacement boards from Tesla, I don't think I want to try to jerry-rig a fix to this one, and I don't really need this unit now anyway, so I think I will put it on Ebay as a "for parts or repair" item. Surely someone needs the cord, plug, contactors, etc.
The picture of the overall unit shows more of the wiring and the power components (fuses?). I have a 20A 240V cord wired in to provide power in the shop.
Thanks again for the help!
 

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The AC input to the top board comes in on the widely-spaced white and blue wires in the white 10-pin header, CNAx, but i can't see from where those wires are sourced.

Is there another large contactor on the underside hidden from view? There appears to be three FETs on the topside near the connector with 1 red and 3 black wires. the red is the 24V supply and the 3 blacks are 3 low-side coil driver returns being switched thru the FETs. Maybe that is to allow for switching 3-phase Mains. i can't tell if there are 3 freewheeling diodes in the vicinity of the FETs, possibly across the coil between the Drain and 24V.

Can you read any part numbers on the distressed parts? Those two white or gray large surface mount parts look like they could be fuses, likely on the 24VDC and RTN that is used for the main contactors. Or they could be the freewheeling diodes mentioned above, although there are only 2. Replace those 2 parts and it may fix your unit.
 

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Discussion Starter #9
I am posting some sharper pictures of the top and bottom sides of the board where the distressed components are. Also clearing up some misunderstandings, before I start scraping off the coating and probing with an ohm/volt meter.
The blue and white wires on the wide white connector come from the lower board, where the big fuses are, but I cannot see what they connect to. Input AC is connected to the upper board via a pair of white wires on a connector on the right corner of the upper board.
The unit is single phase, per the name plate, and there are only two contactors.
I agree the connector with three black and one red wire is driving the contactors.
 

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Discussion Starter #10
CORRECTION, those two pairs of white wires connected to the right corner of the board are actually thermal sensors, screwed to the incoming power terminals so they look like ordinary wire terminals.
 
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