Clean and Protect a Corroded Charging Port

Why this happens

Charging ports collect dust, moisture and road grime, and in humid or coastal areas the metal contacts can form a thin layer of corrosion. That layer adds resistance, so the contact heats up during charging and the charger may stop or fault. Gentle cleaning with the right products, and keeping the port dry and covered, removes the cause.

What you need

Step by step

1. 1

   Switch everything off

   Unplug the charger from the wall first, then from the vehicle. Turn the vehicle's key off and switch off the main switch if fitted. Wait a few minutes. Remove jewellery. The charging port may still be connected to the battery inside, so treat the pins as live even though many BMS designs switch them off when no charger is connected.

2. 2

   Inspect with a torch

   Look into the charging port and at the charger plug. Note dust, mud, moisture, green or white crusty deposits, dark marks, bent or pushed-back pins, and any melted or browned plastic. Photograph it. Melting, charring or loose pins are not a cleaning job; stop and book a service.

3. 3

   Remove loose dirt

   Use a soft dry brush and, if you have one, short bursts from a can of dry compressed air to remove loose dust and grit. Hold the port facing downwards if you can, so debris falls out. Never poke metal objects such as pins, needles or screwdrivers into the port; they can short contacts and scratch plating.

4. 4

   Clean the contacts

   Spray a small amount of electrical contact cleaner onto a cotton bud or the brush, not directly into the port in large amounts. Gently clean around each contact and the plug's pins. For light corrosion, a few gentle passes with the brush and cleaner are usually enough. Do not use water, vinegar, abrasive paper or metal files; they damage the plating.

   Tip: Clean the charger plug as well; a dirty plug soon re-contaminates a clean port.

5. 5

   Let it dry completely

   Leave the port open and the charger unplugged for at least 15 to 30 minutes so the cleaner evaporates fully, longer in humid weather. Wipe the outside of the port and plug with a lint-free cloth. Never charge with a damp port.

6. 6

   Protect against moisture

   If the manual allows it, apply a very thin film of dielectric grease to the rubber seal or the housing rim, not packed into the contact holes. Dielectric grease helps keep moisture out but does not conduct, so too much can interfere with the contact. Check the port's cover or cap closes fully and the seal is not cracked.

7. 7

   Test with a normal charge

   Reconnect the charger to the vehicle and then to the wall, or in the order your manual recommends. Check the charger starts normally. After 20 to 30 minutes, check the plug and port with an infrared thermometer or by holding your hand near them. They should be only slightly warm. Log the date of cleaning.

How to tell it worked

The port and plug look clean and dry, the charger starts normally and the connection stays only slightly warm during charging.

Questions