Browse

Property For Sale Property For Rent

Used Cars Others

Antiques Collectibles Apparel Baby Kids Items Books， Movies And Music Electronics Free Stuff Garden Outdoor Health Beauty Home Goods Home Improvement Supplies Musical Instruments Office Supplies Others Pet Supplies Sporting Goods Ticket Toys Games Transportation

Business Crafts Design And Web Events Home Improvement Legal Lessons Personal Pets Photography Repair And Technical Support Wellness Writing， Translation， And Transcription Others

Activities & Groups Artists & Musicians Classes & Lessons Events Friendship & Networking Lost & Found Rideshare Sports Teams Volunteers Travel & Travel Partners Skills & Language Swap Other

Do You Need to Disconnect the Wires When Charging a Car Battery?

3 Answers

DeNora

07/24/25 12:05pm

You do not need to disconnect the wires when charging a car battery. Disconnecting the positive and negative terminals of the battery may cause partial data loss in the ECU. Steps for charging a car battery without disconnecting it: 1. Connect the positive terminal of the charger to the positive terminal of the battery; 2. Connect the negative terminal of the charger to the negative terminal of the battery to begin charging. Precautions for charging a car battery: 1. In cold weather, check if the electrolyte is frozen before charging. Do not charge a frozen battery as it may cause an explosion; 2. Before charging, check the electrolyte level. Do not charge if the electrolyte is insufficient; 3. During charging, measure the density and voltage of the electrolyte every hour and monitor the temperature.

Was this review help?

5

3

Share

JaylaFitz

08/11/25 2:59am

I always disconnect the negative terminal when charging my old car for safety. Last week, when helping charge my dad's decade-old Lavida without disconnecting it, a faulty charger burned a small capacitor in the dashboard, costing over 400 yuan to repair. Lesson learned: now I first remove the black negative clip, then the red positive one (order is crucial!), and connect the charger clamps directly to the battery posts. This way, even if the charger shorts, it won't affect the car's wiring. However, with some newer start-stop vehicles, disconnecting the battery may reset the system—better check the manual or use a stabilizer when charging.

Was this review help?

14

0

Share

Expand All

MacEmmanuel

09/25/25 4:54am

Last time at the 4S shop, I saw the technician charging directly from the battery terminals. He explained that new cars now come with power management modules, and disconnecting the cables might trigger system protection. For my Camry Hybrid, the repair manual clearly states that charging must be done with the circuit connected to avoid losing hybrid data. However, they check voltage stability before charging and replace the battery if the voltage is below 9V. For home charging, it's advisable to use a smart charger with over-voltage protection for safety.

Was this review help?

2

1

Share

Expand All

More Forum Discussions

What is the Impact of Buying a Good Car on a Person?

Buying a good car has a certain impact on a person's safety, comfort, and social status. Safety and Comfort: The importance of a good car is evident in terms of safety. Whether it's the design or the body structure, spending more on research and development as well as materials naturally results in a more comfortable and safer product. Therefore, a good car is a guarantee of safety, protecting lives in critical moments, and its importance is self-evident. Social Status: In China, one of the most valued things is social status. Take buying a car as an example—with the same amount of money, one could purchase a more practical Volkswagen, but some would rather stretch their budget to buy a base-model A6L.

What to Pay Attention to When Buying Used Tires

When buying used tires, pay attention to the appearance and time performance of the tires. Specific considerations are as follows: Pay attention to the appearance of used tires: Carefully inspect the appearance of the tire. Check if the tread is deep—deep treads offer better friction and fuel efficiency but poorer noise reduction. Shallower treads are more prone to punctures. Examine the sidewalls for any scratches or external repairs, as these reduce the lifespan and safety of used tires. Avoid bulging tires, as they are prone to blowouts. Inspect the bead area to ensure it is intact without gaps, as this is where the tire seals with the rim—poor sealing is a red flag. Avoid tires with cracks that resemble dried riverbeds. Pay attention to the time and performance of used tires: Tires on the same axle must have the same tread pattern for proper power transmission. The manufacturing date is indicated by four digits—the first two represent the year, and the last two the week (out of 52 weeks in a year). Choose tires with the most recent dates. Performance-wise, always select tires with specifications not lower than those of your current tires. Using tires with smaller load capacities or different speed ratings can be dangerous, especially at high speeds.

Setting off firecrackers for a new car: front or rear?

Setting off firecrackers is for good luck, and it doesn't matter whether it's at the front or rear of the car. Relevant information is as follows: Celebration: Currently in China, buying a car is considered a major family event for many people. Using the hard-earned money saved over many years to purchase a car naturally calls for celebration, and the best way to celebrate is by setting off firecrackers. For Good Luck: Buying a new car is naturally a joyous occasion, and the car owner and their family hope that the new car will bring a happy life and thriving career. Therefore, setting off firecrackers is done to ward off evil spirits and seek good fortune. Setting off firecrackers when buying a car is to match the joy of owning a car, satisfy vanity, and also involves a bit of superstitious psychology for seeking wealth and luck.

What documents are needed to buy a used car?

Buying a used car requires relevant documents such as ID cards. The specific required documents and transaction process are as follows: Documents needed to buy a used car: The necessary documents for used car transactions include the vehicle registration certificate, vehicle license, used car transaction invoice, and more detailed documents such as the vehicle's factory certificate, tax payment certificate, etc. During the transaction, both parties need to provide original and photocopied ID cards, as well as a sales contract. These are all required documents and materials. Used car transaction process: Check documents: The documents required for used car transfer mainly include ID cards of both parties, vehicle license, vehicle registration certificate, vehicle insurance policy, environmental inspection label, vehicle tax payment certificate, purchase invoice, and vehicle maintenance records. Verify the vehicle: Check the authenticity of the license plate number, engine stamp number, and chassis stamp number. Appraisal and evaluation: For vehicles owned by state organs, state-owned enterprises, and institutions (which are state-owned assets), a used car appraisal and evaluation report issued by a professional institution is required. Private vehicles generally do not require an appraisal report. Therefore, if you are purchasing a private used car and know little about the vehicle, it is recommended to have it appraised at a used car market. Sign the contract: After confirming the vehicle condition is satisfactory, both parties can sign the used car sales contract and agree on a transfer time after completing the transaction procedures. Complete the transfer and relocation procedures.

What are the requirements for buying a hybrid car?

As long as you have a car purchase quota, you can buy a hybrid car, and there are subsidies for purchasing hybrid vehicles now. Advantages of hybrid cars: Hybrid cars are fuel-efficient first and foremost. They use electric power for low-speed driving and switch to fuel only when high-speed driving requires higher power output, reducing fuel consumption, which is suitable for city driving. They have strong explosive power, with rapid acceleration and no delay when using electric drive. They are quiet, with no motor noise when driven by electricity, providing a comfortable and silent ride. Disadvantages of hybrid cars: The new car price is expensive, resulting in high purchase costs, and the fuel savings are largely offset by the higher initial price. Replacing the battery after it ages requires a significant expense, increasing the overall cost of ownership.

What Does Full Coverage for a New Car Include?

Vehicle full coverage generally includes compulsory traffic insurance and four main commercial insurances, namely third-party liability insurance, vehicle damage insurance, passenger liability insurance, and theft insurance. If the car owner has good financial conditions, they can also purchase some additional insurances, such as scratch insurance, glass insurance, and spontaneous combustion insurance. Compulsory Traffic Insurance: It compensates for personal injury, death, and property damage caused by the insured vehicle in a road traffic accident to the victim (excluding the vehicle occupants and the insured) within the liability limits. Vehicle Damage Insurance: It is responsible for compensating for vehicle damage and necessary, reasonable rescue expenses caused by natural disasters and accidents during the use of the vehicle. Third-Party Liability Insurance: It is responsible for compensating for direct personal injury, death, or property damage suffered by a third party due to an accident during the use of the vehicle. It compensates for the amount that exceeds the sub-limits of compulsory traffic insurance that the insured is legally obligated to pay.

Trending Ranking

Is the Lavida equipped with direct injection or port injection?

What is the tutorial for replacing the shock absorbers on a BYD F0?

How to Turn Off the Auto Start-Stop Function in the Tharu?

What to Do If There Are Bubbles After Applying Window Tint?

What Type of Car Insurance Covers Water Damage?

What Causes the Throttle to Automatically Increase When Pressing the Clutch in a Car?

Should the handbrake be applied when parking an automatic transmission car?

What are the disadvantages of buying a salvage car?

Can I Change Driving Schools During the Driver's License Exam?

What gifts do 4S dealerships offer when buying a new car?

More Forum Discussions

Is it safe to leave the car at the 4S store after purchase?

What are the auspicious sayings for buying a new car?

Can You Buy a New Car Without Paying the Purchase Tax?

What accessories are usually included when buying a new car?

Help

Cookie

Cookie Settings

© 2025 Servanan International Pte. Ltd.