Tesla has revolutionized the electric vehicle industry. Most Tesla models are capable of charging at 40 to 50 amps. However, some Tesla owners have reported that their vehicles charge at only 16 amps.
There are several reasons that can cause Tesla only charging at 16 amps such as
- Limited Power Source
- Limited Charger Charging Rate
- Battery Condition
- Limited by Software
- Power Conversion System (PCS) Failure
In this article, we will explain why your Tesla may only be charging at 16 amps, as well as how to troubleshoot and resolve the issue.

What is the Normal Charging Rate for a Tesla?
Firstly, the normal charging rate for a Tesla depends on several factors, such as:
- The type and size of your battery
- The type and capacity of your charger
- The voltage and amperage of your power source
- The temperature and state of charge of your battery
- The software settings and preferences of your car
At Regular Parking Area
Wall Connector

Generally, at home, the fastest charging speed for your home or office is achieved with a Tesla Wall Connector, which adds up to 44 miles of range per hour charged.
Mobile Connectors and Adapters

Instead of installing a Wall Connector, you can purchase a Mobile Connector and connect it to any three-prong, 120-volt outlet.
A 120-volt outlet can charge a vehicle between two and three miles per hour. This option should work for overnight charging and short daily distances of 30 to 40 miles.
Additionally, you can purchase an adapter set to charge your device with other receptacle types, such as 240-volt outlets.
A 240-volt receptacle, which is typically utilized in homes to power larger appliances, can provide up to 30 miles of range per hour of charging.
On the Road
When traveling in your Tesla or away from your usual parking spot, there are three primary charging options and rates available to keep your vehicle charged.
Tesla Supercharger:
The Tesla Supercharger is the fastest charging option when you’re away from home, allowing you to charge your car up to 200 miles in 15 minutes.

Destination Charging:
The Destination Charging network consists of hotels, restaurants, vineyards, and resorts that host Wall Connectors for consumer charging. Over forty thousand Wall Connectors have been installed by Tesla Destination Charging.

Third-Party Charging Station:
Third-party charging stations can also be located through Plugshare.com. Charging stations labeled as J1772 will work with an SAE J1772 adapter, and 120 volts stations labeled as 120 volts will work with the Mobile Connector.
When not in use, Mobile Connectors should be stored in the trunk for convenient access. For optimal mobility on the road and charging from a 240-volt receptacle, keep an adapter bundle in the trunk.
What Are the Reasons Behind Tesla Only Charging at 16 Amps?
There are several possible reasons why your Tesla may only be charging at 16 amps. If you are experiencing a slow charging rate of 16 amps on your Tesla, here are some reasons behind the problem and steps to troubleshoot and fix the problem:
1. Limited Power Source
If you are using a power receptacle with a low voltage or amperage, such as a 120 volts household outlet or 240 volts with 20 amps outlet, your Tesla will adjust its charging rate to match the available power. This is to prevent the circuit from becoming overloaded and triggering the breaker.
The Fix:
Check the voltage and amperage of your power source by looking at the label on the outlet or the breaker panel. Make sure that you are using a power outlet that has a high enough voltage and amperage to support your car’s maximum charging rate.
Ideally, it would be best if you used a dedicated 240 volt / 50-amp circuit with a NEMA 14-50 outlet for optimal charging speed and efficiency.
If you are using an extension cord or an adapter, make sure that they are rated for high current and compatible with your charger.
2. Limited Charger Charging Rate
If you are using a charger that has a low output capacity, such as the Mobile Connector with a NEMA 5-15 adapter, your Tesla will also limit its charging rate to match the charger’s capability.
The Fix:

Check the output capacity of your charger by looking at the label on the adapter or the cable. Make sure that you are using a charger that has a high enough output capacity to match your car’s maximum charging rate.
Generally, use the Tesla Wall Connector or the Mobile Connector with a NEMA 14-50 adapter for optimal charging speed and efficiency. If you are using a third-party charger, make sure that it is certified by Tesla and compatible with your car.
3. Battery Condition
If your battery is very cold or very hot, or if it is totally full or empty, your Tesla will reduce its charging rate to protect the battery’s health and longevity.
This is because extreme temperatures and states of charge can affect the battery’s performance and lifespan.
The Fix:
Check the temperature and state of charge of your battery by looking at the dashboard or the app. Make sure that your battery is in good condition and at a moderate temperature and state of charge.
Generally, charge your car when the battery is between 20% and 80% full and when the outside temperature is between 50°F and 90°F. If your battery is too cold or too hot, you can try to warm it up or cool it down by driving your car or using climate control.
If the battery is too full or too empty, you can try to adjust your charging limit or schedule to avoid overcharging or undercharging.
4. Limited by Software
If you have set a lower charging limit or a scheduled charging time on your car’s software, your Tesla will also lower its charging rate to comply with your settings.
Tesla limits the charging because you may want to save energy costs by charging at off-peak hours, or you may want to extend your battery’s life by avoiding overcharging.
The Fix:
Check and adjust your charging limit and schedule by tapping on the battery icon on the touchscreen or by using the app.
Ensure that you have not set a lower charging limit or a scheduled charging time that may affect your charging rate.
If your charging period is scheduled and you cannot increase your charging amp. Then,
- Delete the scheduled charging.
- Allow the vehicle to charge for two to three minutes to reach the maximum charging speed of your charger and vehicle.
- Then you can stop it and set a new charging schedule.
However, set your charging limit to the amount of range that you need for your daily driving and your scheduled charging time to the off-peak hours when the electricity rates are lower.
Also, check for any software updates that may improve your charging performance.
5. Power Conversion System (PCS) Failure
The Power Conversion System (PCS) is a component in Tesla vehicles that controls AC and DC charging and supplies 12V DC. Some Tesla owners have reported PCS failures, which can result in reduced charge rates and error messages when charging.
The Fix:
If Power Conversion System (PCS) is faulty, it might need to be changed. If you still have a warranty available, you can claim the warranty by contacting Tesla.
The PCS is not covered under the battery warranty, but rather the basic 50,000 miles or 4 years warranty.
In some cases, Tesla has issued a service bulletin to replace the PCS with an updated component on certain Model 3 vehicles. PCS-related issues may cause the E-fuse to open, preventing the 12V battery from being recharged.
Related Post: Tesla Charging at Electrify America: What You Need to Know?
Frequently Asked Questions [FAQs]
What is the maximum circuit breaker, and how does it affect charging?
The maximum circuit breaker is the highest amperage that the electrical circuit can safely handle, and if it is too low, it can limit the charging rate of a Tesla.
How can I tell if the Power Conversion System (PCS) is faulty?
If your Tesla is only charging at 16 amps and you have ruled out other potential causes, then a failure in the PCS may be the cause.
Can I fix a failure in the Power Conversion System (PCS) myself?
It is not recommended to attempt to fix a failure in the PCS yourself, as it is a complex component and requires specialized knowledge and tools.