Light switch fuse

[Touchofginge]

Hi. When ever I turn on my lights the fuse for the light switch blows. I saw in another thread to use a 7.5amp fuse but that blows as well. Is it worth replacing the switch itself? Or any other ideas?

[ApertureS]

If the fuse blows then something is short circuiting, youll need to narrow it down, what light position is causing it to blow?

[Touchofginge]

9 minutes ago, ApertureS said:

If the fuse blows then something is short circuiting, youll need to narrow it down, what light position is causing it to blow?

It’s not blowing the fuse now. I went through 3 fuses earlier today  and it was as soon as I turned the light switch the light on the switch came on and I could hear the fuse blow. Yesterday was the same as soon as I turned on the lights the fuse went. 

[Touchofginge]

It has happened a couple of times in the last month and I’ve changed the fuse and it’s worked again. Today I put 3 in and blow each time till now and it’s working okay. Engine was off earlier when they blew! Not sure if that helps. 

[Touchofginge]

On 19/07/2022 at 20:08, ApertureS said:

If the fuse blows then something is short circuiting, youll need to narrow it down, what light position is causing it to blow?

When I drove it today. Had the car on sidelights parked for about 15-30 seconds. Put it in reverse and started going back and fuse blew. 

[inspectorman]

Can't see a pattern in your statements pointing to a particular light position. But, at 8 years old, good practice to get all the bulbs out of their holders and inspect the bulbs and holders for unpleasantness. Any corrosion or darkening of the bulb glass should get them replaced. Don't forget the number plate bulbs.

 

Switches do die. £20 will get you another. Is there only one fuse for the entire lighting circuit? The 2014 Rapid manual I'm looking at has ten separate fuses covering the lights (dependent on what's fitted). Which one are you replacing?

 

[Touchofginge]

10 minutes ago, inspectorman said:

Can't see a pattern in your statements pointing to a particular light position. But, at 8 years old, good practice to get all the bulbs out of their holders and inspect the bulbs and holders for unpleasantness. Any corrosion or darkening of the bulb glass should get them replaced. Don't forget the number plate bulbs.

 

Switches do die. £20 will get you another. Is there only one fuse for the entire lighting circuit? The 2014 Rapid manual I'm looking at has ten separate fuses covering the lights (dependent on what's fitted). Which one are you replacing?

 

Thank you for your reply. The fuse I’m replacing is 35 which covers switch illumination, parking lights and number plate lights. After the fuse went this morning when turning on the side lights. I did remove the side light bulbs they look fine and went for a hour drive with no problems. Just went for a five minute drive with them still out and no problem. Then I put them back in and the fuse blew again within seconds. I’ll pop to the shops later and buy some new bulbs to see if they are the problem. 

[inspectorman]

Progress! Have a good look inside the holders, too.

[Touchofginge]

On 21/07/2022 at 17:35, inspectorman said:

Progress! Have a good look inside the holders, too.

Changed the bulbs. Worked fine for an hour and half drive. I got my hopes up thinking that was it but Then went out again and the same fuse blew again. The holders and cables I could see looked fine. Any ideas?

[inspectorman]

Number plate bulbs out next. The successful run with no side light bulbs was not the answer.

[Touchofginge]

3 hours ago, inspectorman said:

Number plate bulbs out next. The successful run with no side light bulbs was not the answer.

Okay will try replacing them next. The holders do look fine for the number plate. I have maybe noticed something. On the light switch itself when I turn the lights on only the sidelight light illumination comes on the actual switch. I noticed when the fuse went yesterday the actual light on the bit you turned came on. How should the lights on the switch work? I will put a photo up to show you. 

[Touchofginge]

I’m wrong they do illuminate just very dull. Well replaced the number plate bulbs and checked cables I can see and housing and all looked fine but still blowing fuse. So I guess the last thing the fuse covers is switch illumination. So I guess try a new switch and if that doesn’t work then garage? Any idea on cheapest place to buy the switch? The only ones I can find with the code 5JA941531F is used on eBay. 

[Kenny R]

When you say you removed the sidelight lamps, did you remove and check the rear sidelight lamps also.

[inspectorman]

Yes, the headlight marking on the switch hardly lights up at all.

 

Some other VAG switches like 5JD 941 531 look very similar but would have to be checked for pin markings and connector block dimensions. And I'm not sure if the white nylon female torx connector in the back of the switch is significant or not. Breakers in Bristol with a Rapid?

 

Don't forget the rear sidelights as parts of your checks.

[inspectorman]

Three bulbs in each rear cluster are part of the sidelight circuit

 

[Touchofginge]

1 hour ago, Kenny R said:

When you say you removed the sidelight lamps, did you remove and check the rear sidelight lamps also.

I’ll check them. Didn’t think of them. 

[Touchofginge]

12 minutes ago, inspectorman said:

Three bulbs in each rear cluster are part of the sidelight circuit

 

I didn’t think of the rear ones. As I’m taking it off I’ll just replace all the bulbs. Reading that diagram. I’ll need 2x p21/4w and 2x w3w bulbs. 

[Touchofginge]

15 minutes ago, inspectorman said:

Three bulbs in each rear cluster are part of the sidelight circuit

 

I didn’t think of the rear ones. As I’m taking it off I’ll just replace all the bulbs. Reading that diagram. I’ll need 2x p21/4w and 2x w3w bulbs for each side

[Touchofginge]

On 23/07/2022 at 15:09, inspectorman said:

Three bulbs in each rear cluster are part of the sidelight circuit

 

Replaced all the bulbs bar one in the rear parking. All looked fine though. Bought a cheap switch of Amazon that fitted but still the fuse is going. So guess it’s time to book it in to a garage. 

[CityScout]

Did you get anywhere with it?

[Touchofginge]

On 13/10/2022 at 09:51, CityScout said:

Did you get anywhere with it?

Nope. It seems to do it when the weather is hot and now it’s cooled down it’s stopped tripping. 
 

The car has been looked at by an auto electrician and my local independent vw garage and couldn’t find anything wrong. Replaced all the bulbs and switch. Auto electrician checked all the cables that could be seen without taking the dash apart and we were trying to disconnect different things. But never found the issue and it’s only tripped once in the last month.