Product Archives - Hybrid Auto

It was not clear to me what the function of fusible link assembly was, and so I did some research and wrote this article. Let me know your thoughts on the subject. You might be familiar with fuse and their need in an electrical circuit. Let us look at the importance of fusible links in our vehicles and how they help us in protecting our vehicle from any potential electrical damage. We will start with the basics of fuses and their operation to understand more before going into fusible links. What is a fuse? Fuse is simply an electrical safety device that is used to protect our electrical components in case of high voltage across the electrical circuit. The fuse is generally made up of metal wire or strip that melts easily. The fuse wire melts in case of any high voltages and the current flow across the circuit is disconnected thereby it stops the current from reaching other devices. The fuse is a suicidal or sacrificial device that has to be either replaced or repaired upon failure. The fuse once breaks down makes the circuit an open circuit. Fuses are also called ADS (Automatic Disconnection of supply) as they disconnect the power from a faulty system. In short, fuses are the gatekeepers and bodyguards of our modern electronic world Fusible Links and their need in our vehicles Our vehicles have a huge amount of wiring system connected across accessories and devices. The wirings are used in starters, alternators, alternators, power seats, sound system, head lights, rear tail lights etc. These circuits are protected by various safety devices such as fuses, circuit breakers, fusible links, and relays. A fusible link is a special type of connection that is used in circuits which have high voltage requirement and must resist high power surge across them. It is a short piece of insulated low voltage cable inside an automotive wiring harness. The fusible link melts and protects the harness during the overload conditions. Fuse Vs Fusible Link Now let us discuss how the fusible link varies from the fuses and the advantages of using fusible links instead of fuses. Both the fuses and fusible link perform the basic function of protecting the devices from damage due to high current overload. The fuses are used circuits with low current draw whereas fusible links can be used in circuits which require high peak currents momentarily in the automobiles. The fuse while breaking down may cause spark and smoke inside the circuit whereas the fusible link is enclosed inside a block assembly and does not cause any visible spark or smoke in the system. The wire inside the fusible link is enclosed in high-temperature fire-resistant insulation to avoid any hazard when the wire melts. And the fusible link is also easy to install than a block of fuse upon failure. The fusible links are usually not rated in Amperes like the fuses because they are specifically designed to meet the requirements for the circuit standards. The fusible link size is usually measured in "Gauge". The Gauge is a term that is used to measure the wire. The gauge number is inversely proportional to the current carrying capacity. The lower the number higher will be the number of wires. Higher numbers of wires will in turn higher current carrying capacity. The fusible link usually is designed with lower gauge number than the rest of the circuit. This will make the fusible link to be the weakest link in the electrical circuit. Therefore the fusible link breaks down in case of faulty connection and safeguards other systems in our electrical connection. Typically, a 10-guage wire would be protected by a 14-guage fusible link. The fusible link and the cable wire are connected by a parallel connector called crimp just like the image below. The parallel connector must be protected with an electrical tape or heat shrink tubing. A fusible link connected across the wires Diagnosis and replacing a fusible link Next let us look at how to diagnose a faulty fusible link and then troubleshoot it with a new replacement link. Let us consider replacing a Toyota fusible link with OEM part number 82620-33030. An OEM part number is a reference number used to differentiate and identify different parts by the manufacturer. This fusible link is connected between the starter motor and the battery, so whenever the fusible link fails the car won’t start. We would always check the starter motor for failure, when the car doesn’t start and we forget about the fusible link. The fusible link disconnects the power supply to the starter motor in case of breakdown. Toyota 82620-33030 If your car doesn`t start always check for the fusible link first for any blowdown. Then inspect the harness and check for any meltdown or broken wires in the fusible link. Don`t be afraid if you find any wires broken down or melted because the fusible link has performed it`s function to perfection to protect the devices for electrical overload. You can further make sure of the fusible link failures by checking the electrical continuity across the circuit. The electrical continuity can be checked by connecting the Multimeter between the two ends of the fusible link. If continuity exits then the problem is not with the fusible link but elsewhere. Please be sure of multimeter`s continuity setting before diagnosing using it. Once you have diagnosed a faulty fusible link, we have to replace the same with a new fusible link in order to restore our vehicle to normal operation. First look for the fusible link connection across the battery and the fusible link wires have gauge size greater than the standard wires. Then replace the wire in the fusible wire with a wire of same gauge size and length. But it is better to replace the entire fusible link assembly and it may cost just some more pennies. Please don’t use thinner wires while replacing as it may lack the insulation requirements and may cause short-out condition in the wires. Safety must always be our first and foremost priority. Compatible Models Let`s look at the different car models that use the Toyota fusible link model 82620-33030 In their car engines in the following paragraph. Toyota Camry Toyota Vista Toyota Aurion & Toyota Venza Note that this list doesn't include Toyota Prius. Start here to learn more about Toyota Prius. Frequently asked Questions and answers How to determine the size of the fusible link required in our vehicles?The fusible link sizes are determined by a qualified and experienced harness engineer who works on the circuit and it depends upon a number of factors. Well, we have a standard fusible link type for our vehicle and we can replace the same fusible link in case of failure. Never attempt to change the type of fusible link in your vehicle.Can we replace the fuses with the fusible links in our vehicles? It should be usually avoided. We can change the fuses to fusible link with the vehicle factory service persons only and it depends on the circuit used in the devices. But safety and liability issues may arise. How are fusible links rated? Fusible links are not rated in amps like the fuses as they designed to meet specific requirements of the circuit in the vehicle. But we can find the compatibility of the fusible link and vehicles in which it can be used. For example, Toyota 82620-33030 is used in Toyota Camry vehicles.Can a blown fusible link be replaced with a MAXI fuse? In some latest model vehicles, the MAXI fuses have replaced the factory installed fusible links. But they don’t have the performance of the fusible link and are replaced only by vehicle factory authorized personnel and not by the individuals. Fusible links are still the best option to use in the starting applications owing to their safety and design requirements till date. Is there any guideline to choose a fusible link? Usually, the fusible link of four gauge sizes higher than the standard wire size is chosen in the circuits. A 6-gauge wire connection will need a 10-guage fusible connection and 10-gauge wire connection needs a 14-gauge fusible link and it goes on. And the length of the fusible link must not exceed 9 inches in length. Do fusible links have any standard regulations regarding their specifications? Yes, the fusible links have specs such as wire size, length, conductors, insulation, etc. are identified and tested as per SAE specification J156. SAE stands for Society of Automotive Engineers. R