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Roadster Charger not working - how to take it apart?

Have a bit of a situation here. Had my roadster delivered today from Germany, where I left it at a roadster specialist to ship. When I tried charging the roadster with the wall adapter (sorry, new here, don't know the technical name yet, is it a UMC?), the roadster seems to think it's not connected. It seems like the adapter might have stopped working, even though the roadster specialist told me he charged the roadster briefly with it before it was picked up. When plugged in I feel "current" on metal surfaces of the roadster - the adapter, the handbrake, etc. I've tried a couple different plugs and same result in all. Starting to get worried because battery is running low after shipping. Any suggestions?


- At work I have electronics technicians that could take apart the adapter and check to see if a wire has gone loose. Are there any manuals or guides on how to do this and what to look for?

- Plan B is to borrow a CAN EU from a friend and go charge at a station, but I might be too far from one, so plan C:

- Plan C: Is it possible to cut a Type-2 cable and splice a wall plug onto it (again technician would do this)

- Plan D: the roadster connector seems like more of a hassle than anything else. I know there's the EU CAN, but don't love the dongle life, and that it can be easily stolen. I've heard of people replacing the roadster charger port with a type-2 charge port (it can be reversed to restore originality, don't worry). Has anyone done it and has it been documented?


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I hesitate to ask, but since the picture you included doesn't show it, are you sliding the gray button towards the car? It won't charge until you do.

If that's not the issue, then look at the body of the charger and tell us if the green/red lights are lit and/or blinking. The UMC also has a "reset" button on it - worth trying that as well.
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Ok, yep, I'm an idiot. I had initially pushed the slider forward, but for some reason the first time I tried charging, it didn't work. I tried at a different place and now it did work. I wasn't sure if pushing it forward was the right thing to do, as the light in the chargeport would turn off.

thank you all for the help


Active Member
Jun 7, 2011
...I know there's the EU CAN, but don't love the dongle life, and that it can be easily stolen.
The CAN EU has the option to lock it to the car with a small padlock. In fact all three versions of CAN adapters have this feature.

When discussing charging equipment, here are some common terms. I admit I had to laugh when I heard "wall adapter.":)

Connector. The piece that actually plugs into your car that has a cable attached to it is called a "connector". There are several types of connectors including Roadster connector (shown in your pic in post 1), J1772 (called Type-1 in Europe), Tesla II (modern Tesla connector used in North America), and Type-2 (common 3-phase chargers in Europe, UK, HK, etc.). There are other connectors but I won't discuss them here.

A "Wall Charger" usually refers to a wall or post mounted charging station. In NA all wall chargers have a cable attached with a connector to plug into your car. In Europe some of the Type 2 charging stations have no cable so you have to bring your own. These are called "untethered" vs "tethered".

A "HPC" or High Power Connector is type of wall charger that was Roadster specific; made in the early days of the Roadster. These are no longer made and the term is deprecated when talking about more modern wall chargers.

A "UMC" or Universal Mobile Connector is a portable charger that usually takes the form of a long cable with a plug on one end that plugs into some type of common electrical outlet. On the other end of the cable is a connector to plug into your car. Most UMCs have a small housing with some electronics built into it near the plug end of the cable. Tesla currently sells a couple versions of this and at one time they made a Roadster-specific UMC. You can purchase adapters for both ends of a UMC. For example, your UMC might come with a NEMA 14-50 plug on one end, and you would need an adapter to plug it into a common household outlet (120v in North America). On the other end of the cable that plugs into your car you would need a CAN SR adapter if your UMC has a Tesla II connector.

A "SMC" or Spare Mobile Connector is a type of mobile charging cable that can only plug into a common household outlet (120v in NA; 230v in EU). Unlike most UMC cables, it does not need a box of special electronics built into the cable. That's because it doesn't use a pilot signal to let the car know how many amps to pull. When your Roadster senses that it's connected to one of these it only pulls a very small number of amps (15A in NA, 13A in EU). These require special wiring - you can't just splice the two hots and ground wires. Most of these have a GFCI control to test for ground leakage, and you can pretty much count on the GFCI to fail at some point.

An "adapter" is a device that enables you to plug into something different than what your cable is configured for. For example, since this is a Roadster forum, you might use a CAN JR adapter to connect a J1772 charging cable to your Roadster. A UMC might need a different type of adapter (on the other end) to plug into a NEMA 14-50 outlet if it's configured for a 6-50 outlet.

- Plan C: Is it possible to cut a Type-2 cable and splice a wall plug onto it (again technician would do this)
The short answer is "no" but it depends on a number of other factors. All Type-2 cables are required to have passive electronics (usually a resister) installed that enables the charging system to determine the amperage capacity of the cable itself. (We don't have this system in NA because we don't have un-tethered stations.) So if you splice a common wall plug into your cable without changing the built-in resistor then the car would pull way too many amps than your new plug and electrical circuit could handle. Hopefully it would trip the breaker before it burned your house down. Having said that, technically it is possible to make such a cable (see SMC paragraph above) if you know what you're doing. I don't recommend it.

Good luck!

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