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Not working Tesla wall charger but works with Tesla EVSE

archon810 said:
Just brought my Gravity home from the showroom, plugged it into my Tesla home charger, and it's not able to charge. Thank you to the people above for some troubleshooting steps and a potential solution.

View attachment 32643
Click to expand...
Out of curiosity - what generation home Tesla charger do you have?
 
Thanks to you guys, I'm back in business with my gen 2 Tesla Wall Connector. 56A didn't actually work for me, I had to step down to 48A. Here's how you do it:
0. Turn off your breaker.
1. Remove the bottom screw with a T10 screwdriver.
2. Pop off the cover using a flathead screwdriver. There are several tabs on each side. Tesla actually cracked my cover when installing in 2019, so be careful.
3. Remove the main screws with a T20 screwdriver to expose this:

1758732413787.webp


4. Put the dial into position 9 for 48A:
1758732375463.webp


5. That's it, put everything back together and flip the breaker back on, then charging should work.
 
I have a Tesla gen 2 wall charger.
Thanks for the instructions @archon810 . I tested with mine set to A (56A) and it worked.

Hallelujah.

14kW sweetness.
My first charge to 100%. Will let it slowly charge up and rebalance the cells.


IMG_0152.webp
 
I have no idea why 56A works for some people but doesn't work for me 🤷‍♂️.
 
It's not the breaker because otherwise it would just trip. I think I have 2x 100A and a 200A panel.
 
Hopefully Lucid fixes this soon. I have two Gen2 Wall Connectors on a 100amp breaker at home, and would hate to have to reprogram one to be just 48/56 amps. I'd really hate to have to reduce both, as my Roadster can charge at 70amps.
 
New forum member here awaiting delivery of an ordered Gravity Grand Touring (GGT).

In my garage I have 2 Gen2 Tesla Wall Connectors sharing a single 100 amp circuit that I've been using for more than 5 years to charge a Model X (limited by Tesla to charging to 48 amps), and an older Model S (with dual 40 amp internal chargers able to charge at 80 amps). This 100 amp circuit for the Gen2 Wall Connectors uses a separate power company meter with time-of-day pricing, enabling much lower rates after 1 am, so I've configured both Teslas to start charging after 1 am. The pair of Gen2 Wall Connectors have a wired signaling link cable between them to permit load balancing when simultaneously charging both Teslas.

I just sold the Model S. I want to home charge my upcoming GGT using one of my Tesla Gen2 Wall Connectors, while continuing to charge my Model X on the other Gen 2 Wall Connector -- with load balancing of the 100 amp circuit as before. How can I do this (safely)?

The primary issue is that the GGT requires J1772 signaling for home AC charging, whereas Tesla's Gen2 Wall Connectors only support Teslas old proprietary signaling based on CANBus. That's why you can't just plug the Gen2 Wall Connector's NACS physical connector into the GGT and expect it to work -- the signaling "handshake" doesn't occur despite the GGT having a NACS physical charge port. (While setting a single Wall Connector's configuration to 56 amps may work for some Gravity owners, it bypasses safety control signaling -- I don't want to burn my house down if anything overheats, and this likely disables load balancing between my pair of Gen2 Wall Connectors.)

So...what I'm thinking of doing to charge my GGT is: Tesla Gen2 Wall Connector <--> TeslaTap Mini adapter (80 amp) <--> J1772 to NACS physical adapter <--> GGT

The $300 TeslaTap Mini adapter bi-directionally converts the Tesla vs. J1772 signaling and control protocols to complete the handshake, but unfortunately for the Gravity also converts the NACS physical plug to a J1772 physical connector (which would be fine for an Air, but not for Gravity). That's why a passive J1772 to NACS physical adapter is also needed to convert the physical plug from J1772 back to NACS. The good news is that Gravitys all ship with this adapter from Lucid, so it's included for free.

Does this make sense? Has anyone else tried this?
 
Pilotgeek said:
The primary issue is that the GGT requires J1772 signaling for home AC charging, whereas Tesla's Gen2 Wall Connectors only support Teslas old proprietary signaling based on CANBus. That's why you can't just plug the Gen2 Wall Connector's NACS physical connector into the GGT and expect it to work -- the signaling "handshake" doesn't occur despite the GGT having a NACS physical charge port. (While setting a single Wall Connector's configuration to 56 amps may work for some Gravity owners, it bypasses safety control signaling -- I don't want to burn my house down if anything overheats, and this likely disables load balancing between my pair of Gen2 Wall Connectors.)
Click to expand...
Are you sure about all this?

1. You can't set one wall connector to a different Operating Current than the other if they're wired to a single breaker. One will be a Slave, the other sets the max current: Here's some snippets from the manual:
Screenshot 2025-10-12 at 11.54.29 AM.webp
Screenshot 2025-10-12 at 11.55.18 AM.webp



2) Setting the Wall Connector to 56 amps should not disable any safety control signaling. Do you have any links to documents supporting this?

3) I charge my 2011 Tesla Roadster using SR Can adapter from either of my Gen2 Wall Connectors. Do you believe my adapter is going something special, because Roadster was done well before the Gen 2 Wall Connector came out.

4) Do other vehicles have problems with the Gen2 Wall Connector? Obviously, almost all will use an adapter, but I suspect most of those adapters are simple without logic built-in.

I'm going to contact the fellow who made the Tesla Roadster to NACS adapters and see what information I can get out of him. He had worked pretty closely with Tesla on his adapters and should have the best knowledge.
 
Yesterday at the Lucid San Jose grand opening, I mentioned this issue to one of Lucid's chief hardware engineers. He seemed genuinely interested in sorting this out, so I got his email and emailed him a link to this thread. Hopefully, it will be on Lucid's radar now.
 
Pilotgeek said:
New forum member here awaiting delivery of an ordered Gravity Grand Touring (GGT).

In my garage I have 2 Gen2 Tesla Wall Connectors sharing a single 100 amp circuit that I've been using for more than 5 years to charge a Model X (limited by Tesla to charging to 48 amps), and an older Model S (with dual 40 amp internal chargers able to charge at 80 amps). This 100 amp circuit for the Gen2 Wall Connectors uses a separate power company meter with time-of-day pricing, enabling much lower rates after 1 am, so I've configured both Teslas to start charging after 1 am. The pair of Gen2 Wall Connectors have a wired signaling link cable between them to permit load balancing when simultaneously charging both Teslas.

I just sold the Model S. I want to home charge my upcoming GGT using one of my Tesla Gen2 Wall Connectors, while continuing to charge my Model X on the other Gen 2 Wall Connector -- with load balancing of the 100 amp circuit as before. How can I do this (safely)?

The primary issue is that the GGT requires J1772 signaling for home AC charging, whereas Tesla's Gen2 Wall Connectors only support Teslas old proprietary signaling based on CANBus. That's why you can't just plug the Gen2 Wall Connector's NACS physical connector into the GGT and expect it to work -- the signaling "handshake" doesn't occur despite the GGT having a NACS physical charge port. (While setting a single Wall Connector's configuration to 56 amps may work for some Gravity owners, it bypasses safety control signaling -- I don't want to burn my house down if anything overheats, and this likely disables load balancing between my pair of Gen2 Wall Connectors.)

So...what I'm thinking of doing to charge my GGT is: Tesla Gen2 Wall Connector <--> TeslaTap Mini adapter (80 amp) <--> J1772 to NACS physical adapter <--> GGT

The $300 TeslaTap Mini adapter bi-directionally converts the Tesla vs. J1772 signaling and control protocols to complete the handshake, but unfortunately for the Gravity also converts the NACS physical plug to a J1772 physical connector (which would be fine for an Air, but not for Gravity). That's why a passive J1772 to NACS physical adapter is also needed to convert the physical plug from J1772 back to NACS. The good news is that Gravitys all ship with this adapter from Lucid, so it's included for free.

Does this make sense? Has anyone else tried this?
Click to expand...
Agree with @Smorgasbord on need to confirm re/ safety actually being an issue.

I am nowhere near as technical as you, but we have a “regular” load balancer for our J1772 and our Tesla Gen 2 wall connector as we charge our R1S (and now our Gravity) with the J1772 (and a NACS adapter now on one and our Model Xs on the other.

My point is a “cheap” J1772 wall charger with a NACS adapter and load balancer may be easier and cheaper than what you proposed. Also, the Gen 2 Tesla adapters don’t use WiFi, so may be worth the investment to get a new NACS adapter - though I don’t know if there’s really any value in charger firmware updates.
 
Smorgasbord said:
Are you sure about all this?

1. You can't set one wall connector to a different Operating Current than the other if they're wired to a single breaker. One will be a Slave, the other sets the max current: Here's some snippets from the manual:
View attachment 33412 View attachment 33413


2) Setting the Wall Connector to 56 amps should not disable any safety control signaling. Do you have any links to documents supporting this?

3) I charge my 2011 Tesla Roadster using SR Can adapter from either of my Gen2 Wall Connectors. Do you believe my adapter is going something special, because Roadster was done well before the Gen 2 Wall Connector came out.

4) Do other vehicles have problems with the Gen2 Wall Connector? Obviously, almost all will use an adapter, but I suspect most of those adapters are simple without logic built-in.

I'm going to contact the fellow who made the Tesla Roadster to NACS adapters and see what information I can get out of him. He had worked pretty closely with Tesla on his adapters and should have the best knowledge.
Click to expand...
I'm not entirely sure about what I proposed above, which is why I asked if anyone else had tried something similar to charge their Gravity.

I'm still trying to figure out why some owners have been successful in charging their Gravity by setting a single Gen2 Wall Connector to 56 amps. Most of my research into the signaling protocols comes from various AI Internet searches that describe the differences between signaling protocols. For example:

Elaborate on the technical differences between SWCAN and J1772 signaling protocols

The J1772 signaling protocol uses a simple, analog pulse-width modulation (PWM) scheme over a Control Pilot (CP) pin, while the Gen 2 Wall Connector primarily communicates with Tesla vehicles using a more advanced digital protocol called Single-Wire CAN (SWCAN)

. This difference in complexity and design is the root cause of the compatibility issues when a non-Tesla EV attempts to charge with a Gen 2 Wall Connector via an adapter.

J1772
(SAE J1772)
J1772 signaling is a legacy standard known for its simplicity and reliability, operating solely through voltage and resistance levels on the CP pin.
  • Communication method: An analog, 1 kHz square wave signal is sent over the Control Pilot (CP) line.
  • Signaling states: The charging status is controlled by the vehicle's onboard switch, which adjusts the resistance between the CP and Protective Earth (PE) pins.
    • +12V: The EV is not connected.
    • +9V: The EV is plugged in but not ready to charge.
    • +6V: The EV is requesting a charge.
  • Current advertisement: The maximum current the charging station can supply is communicated to the vehicle by varying the duty cycle (pulse width) of the 1 kHz square wave. For example, a 50% duty cycle might indicate a 32A limit, while a 16% duty cycle indicates a 10A limit.
  • Simplicity: This protocol is simple, robust, and requires no complex onboard electronics in the EVSE (Electric Vehicle Supply Equipment). It is purely a handshake between the EV and the charger to determine readiness and maximum capacity.

Single-Wire CAN (SWCAN)
SWCAN is a digital, proprietary communication bus used by Tesla. It operates on a single wire and is fundamentally different from the J1772 protocol.
  • Communication method: A digital, packet-based protocol is used for communication. Unlike the analog J1772 signal, SWCAN can transmit more complex data and commands, allowing for features like remote access control and diagnostics.
  • Enhanced functionality: In the Gen 2 Wall Connector, SWCAN is used for several advanced features that J1772 cannot support:
    • Authentication: The Gen 2 Wall Connector can authenticate a Tesla vehicle by its VIN, allowing for more advanced access controls.
    • Power sharing: It enables communication between multiple Wall Connectors to intelligently share power from a single circuit.
    • Diagnostics: It allows the Wall Connector to report internal diagnostics and status to the vehicle and Tesla's servers.
  • Initial handshake: A Gen 2 Wall Connector will first attempt to initiate a charging session using the more advanced SWCAN protocol. It will only fall back to the basic J1772 protocol if the SWCAN handshake fails.

The incompatibility problem
This handshake fallback process is the source of the compatibility issues. When a non-Tesla EV uses a NACS-to-J1772 adapter with a Gen 2 Wall Connector:
  1. SWCAN signal interference: The non-Tesla EV's onboard charger may "see" or misinterpret the initial SWCAN packets from the Wall Connector before the J1772 fallback occurs.
  2. Mismatched expectations: The EV's charging control module might not properly handle this unexpected digital communication, causing it to fail the initial handshake and terminate the session.
  3. Timing issues: Slight variations in timing or signal characteristics between different adapter brands and vehicle models can exacerbate this problem, leading to inconsistent or failed charging sessions.
  4. Adapter role: High-quality adapters, like the TeslaTap, contain additional circuitry to filter out the SWCAN signal and ensure a clean, standard J1772 protocol is presented to the non-Tesla EV, mitigating most of these issues. Lower-quality adapters may be less effective at this filtering.
 
This TeslaTap blog article describes a bit about how Wall Connectors (EVSEs) and the charger in the car communicate:
Steps in Charging:

1. The charging process begins when you plug the connector from the EVSE into our adapter or your car.

2. The EVSE sends out a signal (duty cycle) on the pilot pin that informs the vehicle what the MAXIMUM amount of power is available at the EVSE. This is to stop the car from pulling to much power and blowing the circuit breaker that feeds power to the EVSE.

3. Once the car sees this signal and it decides that the available power is above the MINIMUM required by the on board charger it will modify the voltage on the pilot pin to inform the EVSE that it wants to activate the contactor (switch) and start feeding power into the onboard charger.
Click to expand...

That said, TeslaTap adapters do have circuitry inside them:

The adapter has a special circuit that allows it to work on any current Tesla charger including Destination Chargers.
This adapter cable has all of the pins needed to maintain full functionality and safety protocols used by Tesla and J-1772 charging systems.
Click to expand...

Maybe we could petition TeslaTap to do an NACS to NACS adapter with the circuitry?
 
Since people have asked about potential safety concerns in using a Tesla Gen2 Wall Connector, please see the result of this query about how an adapter permits a non-Tesla EV like Gravity (with J1772 signaling) to work with a Tesla Gen2 Wall Connector:

Tell me more about how the signaling translation works

The adapter translates the communication between the Tesla Gen 2 Wall Connector, which uses the proprietary NACS signaling, and the non-Tesla electric vehicle (EV), which uses the SAE J1772 standard
. This translation primarily involves the Control Pilot (CP)and Proximity Pilot (PP) signal lines, which the charger and EV use to exchange information about safety and charging status.
Here is a step-by-step breakdown of how the signaling translation works:

Stage 1: Initial connection
  • The EV driver connects the NACS-to-J1772 adapter to the Tesla Gen 2 Wall Connector handle.
  • The driver then plugs the adapter and handle assembly into the non-Tesla vehicle's J1772 charging inlet.
  • Once the physical connection is made, the adapter's internal circuitry becomes active and facilitates the exchange of signals between the two systems.

Stage 2: Handshake and safety checks
  • Proximity Pilot (PP) signal: In the J1772 standard, the PP pin uses resistance to signal the presence of the plug and whether the release button is pressed. The adapter must mimic these resistance changes, so the EV knows a J1772 plug is connected and latched.
  • Control Pilot (CP) signal: The J1772 standard uses a 1 kHz square wave on the CP line to communicate the charging state. The EVSE (in this case, the Tesla Wall Connector) sends a signal, and the vehicle changes the resistance on its end to alter the square wave's voltage and indicate its status.
  • The adapter must correctly interpret the Tesla NACS equivalent signals and produce the required J1772 signals to mimic a direct connection. This allows the Wall Connector to confirm that a valid EV is connected and ready to receive power.

Stage 3: Charging current negotiation
  • The J1772 standard uses the duty cycle of the CP square wave to indicate the maximum charging current the EVSE can provide. A longer high-state pulse (higher duty cycle) means more available current.
  • The Tesla Gen 2 Wall Connector sends its available current information using its own NACS protocol.
  • The adapter's electronics translate the NACS message into the appropriate J1772 duty cycle signal.
  • The non-Tesla EV's onboard charger reads this translated signal and then draws power within the specified limit, ensuring that the car does not demand more current than the Wall Connector can safely deliver.

Stage 4: Safety monitoring and termination
  • Continuous monitoring: Throughout the charging process, the adapter, EV, and Wall Connector constantly monitor the signals to ensure everything is functioning correctly.
  • Disconnection signal: If the EV driver presses the release button on the J1772 connector, the adapter detects this and translates the signal for the Wall Connector. This causes the Wall Connector to de-energize the power lines, preventing dangerous arcing.
  • Termination: The adapter also facilitates the communication needed to safely terminate the charging session when the vehicle is finished or when manually commanded.

Key safety consideration
An essential feature of adapters is thermal protection. If the adapter overheats due to high current, it should have a safety mechanism to communicate with the charging station to reduce or stop the power flow. Quality adapters use internal sensors to achieve this, making the charging process safer for both the vehicle and the charging equipment.
 
Pilotgeek said:
The J1772 signaling protocol uses a simple, analog pulse-width modulation (PWM) scheme over a Control Pilot (CP) pin, while the Gen 2 Wall Connector primarily communicates with Tesla vehicles using a more advanced digital protocol called Single-Wire CAN (SWCAN)

. This difference in complexity and design is the root cause of the compatibility issues when a non-Tesla EV attempts to charge with a Gen 2 Wall Connector via an adapter.
Click to expand...
Interesting. I found this via AI:

Tesla's SWCAN protocol
Tesla's proprietary system, used with its Gen 2 Wall Connector and vehicles, builds upon the basic J1772 signaling by adding a more advanced digital protocol.
  • Initial handshake: A Tesla vehicle and a Wall Connector still use the basic analog J1772 PWM handshake to establish the initial connection and safety checks. The EVSE signals its available current via the PWM duty cycle.
  • Protocol switch: After the vehicle indicates it is ready to charge, the Wall Connector and Tesla EV will stop using the PWM signal. They switch to a high-speed digital Single-Wire CAN (SWCAN) protocol, which runs over the same CP line.
  • Data transfer: The SWCAN protocol allows for a much more detailed and robust two-way data exchange at a faster speed (33.3 kbps). This enables advanced communication features between the charger and the vehicle's onboard battery management system (BMS).
  • Enhanced charging: This enhanced communication allows for features like precise control over the charging process, load sharing between multiple Wall Connectors, and over-the-air firmware updates for the charging hardware.
Click to expand...
The question then is whether the "filtering" needed for Lucid to ignore the additional info provided by the Gen 2 can be done in software, or whether additional hardware is needed.

And this still doesn't answer the question as to why a lower max current Gen-2 seems to work.
 
Honestly, the price of both adapters combined leads me to say… just buy a new EVSE? They’re not all that expensive.
 
borski said:
Honestly, the price of both adapters combined leads me to say… just buy a new EVSE? They’re not all that expensive.
Click to expand...
Well, at least one of us has the shared breaker on a different PGE billing, so who else support load sharing with 2+ EVSE on a single breaker?

My contact who made the Roadster NACS adapters thinks:
• Serial comms were introduced on the pilot signal starting with the Gen 2 chargers.
• The basic pilot signal uses a different translation when it goes above 48A , which might which might have something to do with Lucid's issues above the 48 Amp setting.

So, at least we have some rationale for why setting the Wall Connector to 48A is a valid workaround. And, maybe Lucid can program a fix to understand the different, greaater than 48Amp, pilot signal.
 
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