# EV Charging Error Messages: What They Mean

By EV Charge Cables · Published 18 October 2026

**The short version**

Most EV charging errors fall into a few categories: connection problems, authentication failures, and charger hardware faults, each with a clear first step to try.

- A loose cable connection is the most common cause of a failed session and the easiest to fix.
- Authentication errors usually mean a network app session has expired or payment was declined.
- Overcurrent and ground fault errors are hardware faults on the charger side: report them and move on.

Most EV charging errors fall into a small number of categories: a communication problem between the car and the charger, a fault with the network's payment or authentication system, or an issue with the cable connection itself. Understanding what each type of message means lets you fix the ones you can fix and move on to the next charger without unnecessary stress. Always start by checking that your [charging cable](https://www.evchargecable.co.uk/collections/ev-charging-cables) is firmly seated at both ends before assuming the fault lies elsewhere.

| Error type | Likely cause | What to try first |
| --- | --- | --- |
| No communication / no handshake | Cable not fully inserted, dirty contacts, or car not ready | Unplug, wait 10 seconds, reconnect firmly |
| Authentication failed | RFID card not recognised, app session expired, or payment declined | Re-open the app, try contactless card instead |
| Charging stopped unexpectedly | Network outage, temperature protection, or car schedule conflict | Check car settings; try a different charger |
| Overcurrent / ground fault | Charger hardware fault or protection triggered | Do not retry; report to the network helpline |
| Cable lock error | Mechanical lock jammed, connector damaged | Check connector for damage; contact network support |
| Charge limit reached | Car is set to charge to a specific level (e.g. 80%) | Adjust charge limit in car settings or app |

### Why does my EV say "not charging" even though it is plugged in?

This is one of the most common issues and usually has a simple cause. First, check that the cable is clicked firmly into both the car and the charger. A partial connection can fool the car into thinking it is plugged in while no power is flowing. Second, check whether the car has a charging schedule set: many EVs default to starting charging at a set time (often overnight off-peak), which can prevent immediate charging when you expect it. Adjusting or disabling the schedule in your car's settings or its companion app usually resolves this quickly.

### What does an authentication or payment error mean?

Authentication errors at public chargers mean the charger could not verify your identity or payment method. This can happen when an RFID card is presented too quickly or at an angle, when a network app session has timed out, or when a payment has been declined at the point of authorisation. Try these steps in order: re-open the network's app and start a new session; try a different payment method, such as a contactless bank card; and if the charger accepts RFID cards, try tapping again more slowly. If none of these work, the charger likely has a back-end connectivity fault and is worth reporting to the network.

### Why did my charging session stop before the battery was full?

Several things can interrupt a session mid-charge. A network connectivity fault at the charger is the most common cause at public sites: the unit loses contact with the network's payment servers and ends the session as a safety measure. On the car side, high battery temperatures can trigger the car's thermal management system to slow or pause charging to protect the cells. Some cars also end a session automatically if they reach their programmed charge limit. Check your car's charge log in the companion app to see whether the session ended at a set limit, which would point to a car setting rather than a charger fault.

### What are ground fault or overcurrent errors, and are they dangerous?

These are hardware-level protection faults. A ground fault means the charger detected an unexpected electrical path to earth, often caused by moisture ingress or a damaged component inside the unit. An overcurrent fault means the charger detected a current outside normal operating bounds. Both cause the charger to shut down immediately as a safety measure, which is the correct response. Do not attempt to restart the charger or keep retrying. Move to a different charger and report the fault using the number printed on the unit. These faults are internal to the charger and are not caused by your car or cable.

### What should I do if my cable will not unlock from the charger?

Most EV connectors lock into the car during charging and release when the session ends. If a cable will not release, try unlocking the car with the key fob or the car's app, as the lock is often linked to the car's central locking rather than the charger itself. If the connector is locked by the charger rather than the car, this is a mechanical fault on the charger side: call the network's helpline immediately. Do not force the connector out, as doing so can damage both the connector and the car's inlet. Keep the network's phone number to hand: it is usually displayed on the charger unit.

### How can I reduce the chance of errors when using public chargers?

A few habits help considerably. Inspect the connector before plugging in: look for obvious damage, corrosion, or debris on the pins. At untethered AC chargers, make sure your own cable is in good condition. Carry a backup payment method so that if one network's app fails you can pay by contactless. Knowing which networks work on your regular routes, and having their helpline numbers saved, means you spend less time troubleshooting and more time charging.

- Keep your cable's connectors clean and dry
- Check the charger's screen for instructions before tapping your card
- Disable charging schedules before a public session if you need to charge immediately
- Report every fault so the network can fix it for the next driver

### Frequently asked questions

#### My car shows "charging paused" but the charger looks active. What is happening?

This usually means the car has received a signal from the charger but has paused for a reason on the car side. The most likely culprits are a charging schedule conflict, a user-set charge limit that has already been reached, or a thermal management pause. Check the car's companion app for the active charge status and any notifications about why charging was paused.

#### Can a faulty cable cause charging errors?

Yes. A cable with damaged pins, a bent contact, or a worn seal can cause intermittent communication faults that appear as "no handshake" or "communication error" messages. If you see recurring errors across multiple chargers, inspect your cable carefully. A quality replacement from a reputable supplier is far safer than persisting with a damaged cable. Browse our [charging cable range](https://www.evchargecable.co.uk/collections/ev-charging-cables) if you need a replacement.

#### Why does fast charging work at some chargers but not others?

Every charging session is limited by whichever is lowest: the charger's maximum output, the car's maximum charge rate, or the battery's current state. If a charger shows a lower speed than expected, it may be operating in a reduced mode due to grid demand, high ambient temperature, or a partial hardware fault. Check the charger's screen for any status messages, and verify your car's real-time charge rate in the companion app.

#### What should I do if I am stuck and cannot charge anywhere nearby?

First, call the network's helpline: they can sometimes remotely reset a charger. If you have a portable 3-pin charger in the car, a domestic socket at a nearby business or home (with permission) can provide a slow but workable charge. Your breakdown provider may also have EV-specific assistance, so check whether your policy includes roadside charging support.

#### Is it normal for charging to slow down as the battery fills?

Yes, this is by design. Battery chemistry means cells accept charge most rapidly when they are between roughly 20% and 80% full. Above 80%, most cars intentionally reduce the charge rate to protect the battery from stress. This is not a fault and will not appear as an error message. It is why charging from 10% to 80% is much quicker than from 80% to 100%.

#### Can rain or wet weather cause charging errors?

EV charging connectors and inlets are designed and tested for use in wet weather, and charging in the rain is perfectly normal. Pooling water inside a damaged or cracked connector housing is a different matter: if your cable's connector looks cracked or the pins are corroded, do not use it in wet conditions. Charger units at public sites are also weatherproofed, but units with physical damage to the housing should be reported rather than used.

Most charging errors are fixable in under a minute once you know what to look for. For more troubleshooting advice and guides on getting the most from your EV, visit our [Guides section](https://www.evchargecable.co.uk/blogs/guides). And if your cable is showing signs of wear, browse our full [EV charging cable range](https://www.evchargecable.co.uk/collections/ev-charging-cables) to find a reliable replacement.

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Canonical version: https://www.evchargecable.co.uk/blogs/guides/ev-charging-error-messages-what-they-mean

EV Charge Cables, EV charging cables matched to your car: https://www.evchargecable.co.uk. Some links in this article are Amazon affiliate links; as an Amazon Associate we earn from qualifying purchases at no extra cost to you.