The major reasons behind no power to some fuses in fuse box are a bad or dead battery, wiring issues, a faulty ignition fuse, a damaged starter relay, a malfunctioning fuse box, and a bad accessory power relay, and no signal from the ECM.
Keep reading this article to find out more about these issues that cause no power to the fuses in your car and how you can fix them. We’ll also discuss what would happen if there were no fuses in your car. Let’s begin!
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No Power To Some Fuses In Fuse Box [7 Easy Fixes]
We’ll explain how you can fix the main issues that cause no power to fuse in your car in this section.
Note: You can also read how to fix no power from ECM to Fuel Pump relay.
1. Bad Or Dead Battery
The positive terminal of the battery is directly connected to the fuses in your car with a wire. The battery powers all the fuses. But when the battery goes bad, some or all of the fuses will not get power.
So, if you’re wondering why is the car fuse box not getting power, a dead battery is the first thing you should check. You can easily check it with a multimeter and see if you have good voltage. If the voltage isn’t close to 12V, that means the battery isn’t generating enough power.
Solution:
When the battery generates a voltage lesser than 12V but is still close to it, the problem could come from corrosion on one of the terminals. In that case, clean the battery and see if it works.
But if you’re getting no power at all from the battery, it means the battery is dead. You need to replace it with a new one. That will fix your problem and your fuses will be powered once again.
2. Wiring Issues
The power goes from the battery to the fuse via the red wire that’s connected at the positive terminal of the battery. If you find that there are some fuses not getting power, it could be due to a problem with that red wire.
But how can you tell if that wire has gone bad? Check the ignition fuse first. It’s usually the first fuse that gets power in most cars. If there’s no power to the ignition fuse, that means there is an issue with your wiring.
Solution:
First, make sure the connections at the positive and negative terminals of the battery and the fuses are tight. If there is a break in the red wire, you can easily replace it with a new one and connect it to the battery and the fuse.
3. Faulty Ignition Fuse
The ignition fuse is the fuse that gets the power first and it sends that to many other fuses in your vehicle. If the battery and wiring in your car are alright, the next thing you check is the ignition fuse.
Checking an ignition fuse is easy. First, check if the fuse is blown or not. If the fuse is not blown and you’re not sure if it’s working or not, replace it with another fuse of the same amperage and see if it gets power. If the second fuse is getting power, that means the original fuse has gone bad.
Solution:
If the ignition fuse is blown or malfunctioning, replace it with a new one. You can pull the fuse with your hand or use fuse pullers. Replacing the fuse will send power to the other fuses in your vehicle and solve your problem.
4. Damaged Starter Relay
The power in a lot of fuses goes through the starter relay in many vehicles. When the starter relay malfunctions, it’s often accompanied by no power to the starter fuse. So, check the starter fuse as well and see if it’s getting power.
You can test the starter relay by turning the engine and having someone listen for a clicking sound. It’s fine if there’s a clicking noise but it’s damaged if no sound comes from it when the engine is turned.
Solution:
You need to replace the starter relay if it’s damaged. Make sure you disconnect one of the terminals of the battery to prevent electrocuting yourself when replacing the relay.
Just pull out the old starter relay and put a new one in its place matching the pins in the fuse box.
Reconnect the battery again and try to start your car. Your car fuses good but no power problem will be fixed if a damaged starter relay was causing them.
5. Malfunctioning Fuse Box
Sometimes, the fuse block themselves can get damaged and cause the fuses not to get any power.
If you find one side of the fuse box not working properly, it’s a good idea to pull out the fuse box and check underneath it, and look out for any signs of damage in it.
Solution:
If the fuse block is damaged, you need to replace it with a new one. Luckily, fuse boxes aren’t too expensive to replace and a new fuse box will only cost you around $20 – $50 depending on the quality you go for.
6. Bad Accessory Power Relay
A common cause of no power to fuse box Ford is a bad accessory power relay. This relay usually powers all the accessory fuses in your car. When it goes bad, it causes wiring issues as well as problems with the brake lights.
Solution:
You need to replace the bad accessory power relay with a new one. Replacing this relay will no longer keep you wondering why some of my fuses are not getting power if it was the reason that was causing the problem.
7. No Signal From ECM
Sometimes, the ECM can fail to send the signal to the correct fuses due to electrical issues. Your no power to fuse box under hood problem can be caused because of it.
Solution:
Resetting the ECM normally does the trick when there’s no signal from the ECM. Disconnect both the positive and negative terminals of the battery and connect them again after a while. That’ll reset the system and your fuses should work fine after that.
What Happens If There Is No Fuse
The fuse acts as a safety mechanism that prevents the electrical components in your car from being damaged. When there is a short in the electrical circuit, it can lower the resistance and pass a lot of electricity.
The fuse gets blown when that happens and stops the circuit from reaching further and damaging the components. Without the fuse, the electrical current will directly reach the components and damage them.
FAQs:
How does a car fuse get power?
All the fuses in a car are meant to protect certain electrical components and they get their power from the battery in the car. The fuses are connected to the positive side of the battery.
How can I detect a bad fuse?
The fuses have a metal piece inside them through which electricity passes to the different components in a car. The link of the metal piece will be broken when it gets blown or goes bad.
Do fuse boxes only have fuses?
Fuse boxes not only have fuses in them but they also have several relays to control the flow of electricity to the electrical components in a car.
What to do if I can’t get the fuse out of the fuse box?
Modern engines are designed with fuse boxes that are placed too tight and you can’t move your hands around them. Use dedicated fuse pullers, in that case, to pull out the fuses in your car.
Conclusion
No power to some fuses in the fuse box is a frustrating problem as it can even keep you from starting the car in many cases. But now you know the main reasons behind this problem and how you can fix them.
We hope this guide has helped you diagnose the specific reason why there is no power to the fuse boxes in your car and solve it. Drop a comment below if you have any questions about electrical issues in a car.
About John M
John contributed as a technical head at an automobile company just 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, part & product and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.