If your car has loose battery terminal connections, they can cause several problems. The most common symptom is difficulty starting. This is because the loose battery will not be able to provide the necessary current to engage and turn the starter motor. Other symptoms include dim lights and related low voltage electrical problems. On modern vehicles there are various computers and electrical components that are voltage sensitive and even a small drop in voltage will cause them to cease to function properly. This may surprise you, but the automatic transmission is, not only the most sophisticated component on a modern vehicle but, it must have a constant flow of correct voltage to work properly.
If your battery cable is loose, the consequences can be serious and inconvenient. You might lose power and end up stranded or if your battery cable is frayed or damaged, it could cause a short circuit and start a fire. A loose battery terminal can be a real pain, especially if it’s preventing your car from starting, in addition, if your battery cables are loose, they can cause your battery to drain. The reason for this is that when the cables are loose, they can create a small electrical arc that will draw current from your battery causing it to drain.
Loose battery terminals affect the flow of electricity, and a loose battery terminal can cause the car’s electrical components, like navigation, lights, and audio among others to dim or fail completely. This is a common problem and it’s easy to fix. You’ll need a screwdriver, a pair of pliers, and a battery terminal removal tool. The first thing you’ll need to do is identify the problem. If the terminal itself loose, or the connection between the terminal and the battery is loose, you’ll need to use a wrench to tighten the terminal. If it’s the latter, you’ll need to clean the connection and then secure it. Loose battery terminals are relatively easy to fix. First, remove the negative terminal (black) and then the positive terminal (red). The negative side of the battery is also the grounding side of the vehicle’s electrical system. Disconnecting this one first eliminates the possibility of sparking or arching. Clean the terminals with a wire brush and then reattach them. Make sure they are tight so that they don’t come loose again. It’s easy to clean or tighten tightening battery terminals without getting shocked, provided you follow a few simple safety precautions. Make sure the battery is turned off and disconnected from any power source, put on a pair of gloves to protect your hands from the acid in the battery, use a wrench to loosen the terminal clamps, use a terminal puller to disconnect the terminal, use a brush to clean the terminals, tighten the terminal clamps, reconnect the battery, and test the connection by trying to turn on the lights. If the light doesn’t work, the connection is not tight enough so you may need to repeat the steps.
If the terminals get corroded and won’t tighten. You can clean the terminals with a wire brush and then try to tighten them. If that doesn’t work, you can try using a battery terminal shim which is a small, thin piece of lead that is placed between the battery terminal and the cable connector. The shim helps to create a secure connection and prevent the battery terminal from moving around. There are several brands of shims such as Schumacher, Uncell, and Installgear. One of the very best is Tech Team’s #809 8 shim https://techteamproducts.com/product/terminal-shims-lead-8-pieces-00809/ https://www.amazon.com/Terminal-Connections-Automobile-Tech-Team/dp/B0815626MS/ref=sr_1_4?crid=4HE9WZ2MIJYP&keywords=battery+terminal+shims&qid=1673199919&sprefix=terminal+shims%2Caps%2C91&sr=8-4 You can look for other options by doing a hey Siri or hey Alexa Google search or watch Tech Team’s video https://www.youtube.com/watch?v=7BrdtxJhChI&t=6s
It’s easy to clean or tighten tightening battery terminals without getting shocked, mostly because it is only 12 volts and it is direct current however, you can take a few extra steps. Make sure the battery is turned off and disconnected from any power source, put on a pair of gloves to protect your hands from the acid in the battery, use a wrench to loosen the terminal clamps, use a terminal puller to disconnect the terminal, use a brush to clean the terminals, tighten the terminal clamps, reconnect the battery, and test the connection by trying to turn on the lights. If the light doesn’t work, the connection is not tight enough so you may need to repeat the steps.
If the problem is a more serious one, such as a cracked or damaged top post terminal, then you will need to replace the terminal. To make this repair you will need to cut the terminal off flush with the top of the battery then drill and tap a 3/8” x 16 hole 5/8” deep into the terminal. Now take a side terminal charging post, these are made by several companies such as Schumacher, Wirthco, and Boao. The best value is Tech Team’s #808 set of 4 solid lead posts https://techteamproducts.com/product/side-terminal-charging-posts-lead-2-pairs-00808/ https://www.amazon.com/dp/B08156827X?ref=myi_title_dp . There are 2 x 17mm negative posts and 2 x 19mm positive posts. Choose the correct one and screw it into the tapped hole you just made and the repair is done. https://youtu.be/ZxpPK-_51Jk