Model Year 20/21 Fuse Tap Acessory Connection

[Bruno Mendes]

Model: Cupra Formentor 2021 2.0 TDI 150HP
Europe - Portugal

Good afternoon,


I would appreciate some guidance regarding the installation of a fuse tap for an accessory (LEDs).


I have a 5V LED kit with a driver that converts from 12V, controlled via an app. The kit is designed to be powered either through USB or through the vehicle’s 12V cigarette lighter socket. In order to reduce visible wiring and make the installation safer and more integrated, I would like to connect it directly to the fuse box using a fuse tap.


The LED kit was tested using a power supply set to 12V (to simulate the vehicle input), and it drew approximately 2.83A. Based on my understanding, I should therefore use a fuse tap with either a 3A or 4A fuse. Since I want the accessory to operate only when the ignition is on, I intend to connect it to a fuse slot that is live only with ignition. The positive wire would be connected through the fuse tap, and the ground would be attached to a chassis bolt.


My main question is whether I should use an empty fuse slot or piggyback on an existing one. I was considering slot SC48 (7.5A – USB charging slot). However, since this is a modern vehicle, I am concerned that this circuit may be shared with other components. For that reason, I am unsure whether it would be safer to look for an unused slot instead.


Additionally, regarding the fuse tap installation: my understanding is that the original vehicle fuse should be placed in the outer/top position, and the accessory fuse (3A or 4A) in the inner/bottom position. Is there also a required direction when inserting the fuse tap itself into the fuse box?
( I can also send pictures , i'm still not doing the installation).



If anyone has specific experience with the 2021 Cupra Formentor, I would greatly appreciate any advice.


Thank you in advance for your assistance.

 

[James_R]

Fuse box - 30 is permanent live, 15 is ignition live.

 

[Bruno Mendes]

Fuse box - 30 is permanent live, 15 is ignition live.

Thank you for your response.


I also would like further clarification regarding which fuse slot I should choose.


Would you recommend selecting an empty slot that has power (although I understand that some empty slots may not actually be wired and would need to be tested), or would it be more appropriate to use an existing slot such as the USB charging fuse?
Also if I use an empty fuse slot, would I only need to install a single fuse for the accessory? Correct? Two fuses are required only when piggybacking an existing slot , meaning the original vehicle fuse plus the new fuse for the accessory, as shown in the image.


Could you please confirm whether this understanding is correct?

I would appreciate your guidance on the safest and most appropriate option.
Fuse box - 30 is permanent live, 15 is ignition live.

 

[Seriously?]

Model: Cupra Formentor 2021 2.0 TDI 150HP
Europe - Portugal

Good afternoon,


I would appreciate some guidance regarding the installation of a fuse tap for an accessory (LEDs).


I have a 5V LED kit with a driver that converts from 12V, controlled via an app. The kit is designed to be powered either through USB or through the vehicle’s 12V cigarette lighter socket. In order to reduce visible wiring and make the installation safer and more integrated, I would like to connect it directly to the fuse box using a fuse tap.


The LED kit was tested using a power supply set to 12V (to simulate the vehicle input), and it drew approximately 2.83A. Based on my understanding, I should therefore use a fuse tap with either a 3A or 4A fuse. Since I want the accessory to operate only when the ignition is on, I intend to connect it to a fuse slot that is live only with ignition. The positive wire would be connected through the fuse tap, and the ground would be attached to a chassis bolt.


My main question is whether I should use an empty fuse slot or piggyback on an existing one. I was considering slot SC48 (7.5A – USB charging slot). However, since this is a modern vehicle, I am concerned that this circuit may be shared with other components. For that reason, I am unsure whether it would be safer to look for an unused slot instead.


Additionally, regarding the fuse tap installation: my understanding is that the original vehicle fuse should be placed in the outer/top position, and the accessory fuse (3A or 4A) in the inner/bottom position. Is there also a required direction when inserting the fuse tap itself into the fuse box?
( I can also send pictures , i'm still not doing the installation).



If anyone has specific experience with the 2021 Cupra Formentor, I would greatly appreciate any advice.


Thank you in advance for your assistance.

In answer to your second question, this may hopefully help:

 

[Bruno Mendes]

In answer to your second question, this may hopefully help:

Thank you for your response.
Do you have any recommendations regarding which fuse slot I should use — an empty slot (if powered) or an existing/used slot?
I would appreciate your advice on the safest and most appropriate option.

Thank you again.