What does the stop-start system do?

Car start stop button icon

In some cars, the stop-start system can be turned on and off via the button or switch with this icon.

In modern vehicles, stop-start systems (also known as idle-stop systems) are used to preserve fuel and reduce emissions while idling. When the car comes to a stop, the system automatically shuts off the engine until it is required to start again.

Since accessories such as the water pump and power steering system require an operating drive belt to work, these systems are usually designed differently in vehicles with a stop-start system. Typically, these will be powered by a smaller electric motor, allowing accessories to function normally when the car is turned off.


Why do stop-start systems require specific batteries?

New AGM batteries for stop-start cars in Hamilton

AGM car batteries can withstand higher levels of stress than standard car batteries.

Having a stop-start system puts a large amount of load on the battery. This happens due to two reasons. Firstly, the battery has to power all electrical accessories when the car has turned off. Secondly, the battery is put under great strain when the engine is restarted again.

For this reason, it is recommended that either AGM or EFB batteries are used for cars with stop-start systems. These batteries support an increased number of charging cycles and can operate correctly under high loads.

Learn more about different battery types


Signs and symptoms of a stop-start battery due for replacement:

Over time, batteries tend to lose their ability to charge. This can cause the following problems to occur:

  • Reduced battery capacity – Your battery may die quickly or unexpectedly. This will mean that it will need jump starting more often.
  • Slow engine crank – When attempting to start the engine, your engine may take longer than normal to crank. In some cases, it may take several attempts to start the engine.
  • Swollen or bloated battery – When a battery is generating excessive heat, its surrounding case will begin to bulge or swell. This is usually a sign that your battery will need replacing soon.
  • Car not starting – As the health of a car battery becomes worse, it can eventually lead to your car not starting at all. When this happens, it will need to be replaced.


Other problems with the stop-start system:

There are several other issues which can cause the stop-start system to not function correctly. The stop-start system relies on various sensors, including the brake pedal position sensor, engine control unit (ECU), and battery sensors, to monitor relevant parameters and determine when the engine should be turned off or restarted. The control module manages the system’s operation based on inputs from these sensors.

When one of these sensors/modules stops working, the start-stop system may stop functioning properly. The car may stay running when you come to a stop, or it may turn off but struggle to start again.


New AGM and EFB Stop-Start Batteries in Hamilton

Is your car in need of a new start-stop battery? If so, we can help! When you bring your car to Grimmer Motors, our team can pick and source a high-quality battery that can maintain the added stress of a stop-start system. We can also provide replacements for the various sensors and components that make the start-stop system function as it should.

For start-stop battery replacement and servicing in Hamilton, contact Grimmer Motors today!


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