For many people including yourself, when the ignition key or push button is pressed, the car engine starts without any hitch.
However, there is always that one time when instead of the cranking and smooth running of the engine, all you hear is a click and if the hood is open you may hear a fuse pop.
Could it be the starter, ignition switch, or something else?
Where do you even start checking?
These are probably some of the many questions you may have in your mind.
Troubleshooting starter fuse problems can take up considerable time.
So, in this post, I have shared likely reasons why the fuse may be blowing, suggested some fixes, and also shared some signs that may point to a blown car starter fuse blow.
Quick answer. if your car starter fuse keeps blowing it, could be that the starter is faulty or shorting or the solenoid. These are just 2 of the possible causes.
Read on for what else may cause the starter fuse to blow.
5 Reasons Why your Car Starter Fuse be Blowing
If your car’s starter fuse is blowing, then it is usually one of the following:
#1. The car has a faulty or shorting ignition switch. If the ignition switch contacts are shorting, then the current draw from the battery will be in excess of the design amount causing the fuse to blow.
Use a good quality meter to check the continuity of the ignition switch for any shorts.
Consult a qualified mechanic for support if you do not know how to do this.
#2. There is a shorting solenoid relay. If there is a short in the solenoid relay, then the high current draw from the battery will cause the fuse to blow to protect the wiring.
Consult a qualified mechanism for support if you do not know how to do this or use a good quality meter to check the resistance of the solenoid relay coil for any shorts.
#3. Shorting wires from the ignition to the solenoid. The car may also have loose or scuffed wires that may be shorting whenever there is vibration. This may explain when replacing the fuse in some cases, it does not blow immediately.
Also, if wires supplying the ignition or solenoid touch the ground then the fuse will blow.
Consult a qualified mechanic to check the wiring for the car’s system for any faults that may be causing the electrical short.
Why the Car Starter Fuse may Keep blowing
If the replacement fuse blows when you replace it then this is confirmation that the underlying problem is still not yet resolved.
Could it be that instead of one fault – a faulty solenoid, for example, there is a second problem, like a wire from the battery supplying power to the starter that touches the ground?
One reason why the fuse may keep blowing is when there are multiple faults and fixing one does not eliminate the underlying problem.
Signs that the car starter fuse has blown
Will a Blown Fuse Stop a Car from Starting?
If the starter fuse blows then the car will not be able to start.
If you turn the ignition, the car’s ignition may click sound, a sign that the starter solenoid has been energized but after that nothing – no cranking or engine start.
Unfortunately, this is just one of the possible reasons why your car may not start.
A dead or flat battery, loose or broken battery cables and others can also stop the car from starting.
The purpose of the car starter fuse
The car starter fuse protects that wiring supplying 12V from the battery to the solenoid switch that then closes the switch motor contacts and also helps engage the starter motor pinion gear with the flywheel to get the car started.
What the fuse looks like
These are blade or plugin fuses with a plastic body that may be rated from anywhere from about 7.5 – 30 A depending on the car.
Where you can find the car starter fuse
Opening the fuse box is usually located near the car battery under the hood. You can use the inside of the fuse box cover to identify which one is the car alternator fuse.
How to Check if the Starter Fuse Has Blown?
Lift the fuse from the holder and inspect the link inside the fuse’s glass case if it is intact or broken.
You can also use a good quality multimeter to check the continuity of the fuse contacts.
A blown fuse will show as an open circuit. Consult a qualified car mechanic if you need assistance.
Does a Car Starter Motor Have a Fuse?
As far as I know, the car starter motor supply is not fused. I am yet to see one that is fused but there could be exceptions.
Part of the reason is that car starter motors can draw extremely high currents in upwards of 150 A depending on the car.
Car starters have a fuse – to protect the wiring from the battery to the solenoid switch.
The supply from the battery to the starter motor is not fused.
Should the starter fuse keep blowing, then it could be faulty with the ignition switch, solenoid relay, or even shorting wiring.