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Horn relay

Question : I HAVE changed my Kenari car horn to an aftermarket one and have experienced blown fuses ( 15A ) quite regularly.

I went to two accessory shops and they told me there are no problems with the wiring.

I noticed, however, that there is this small rectangular box with wires connecting to the horn which states 20/30V.

Can I use a higher voltage, say, 30A fuse ?

Is it safe to drive with a tyre which has a repair patch on the tyre sidewall ? The puncture was caused by nail.

On tyre size, would it be OK to downsize from 185/60/14 to 195/55/15 ? This is within the three percent rule but I'm not sure if this applies to downsizing.

Answer :

1. The small box is a relay and it should be connected such that the horn button energizes the relay and the relay activates the horn.

In this way the load is not taken by the horn button circuit and the fuse does not "blow".

Do not change the fuse to a larger one as the wiring may not be able to take the load.

I suggest that you get a competent electrician to have a look at how the horn was wired and then rewire it to go through the relay.

2. If the nail is a small one and the hole has not caused nay damage to the sidewall casing, it may be acceptable.

However if the nail has caused some tearing and torn cords can be seen, then the tyre should be replaced.

3. This is not downsizing, although the aspect ratio has increased.

You have actually upsized from 185 to 195.

By the way, why do you need such wide tyres on a Kenari ?


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