Fuse for cabin lights in car keeps blowing

[NoRegretsCoyote]

I drive a ten-year-old VW Touran. The cabin lights and electric window controls failed one day and I realised it was a blown fuse. I replaced the fuse but the problem keeps recurring. I just replace the fuse every week or so. It's an inconvenience but the fuses are about 50c each. (They are small 10W ones).

I can take it to the garage for a diagnostic check but this won't be cheap. Is there any obvious problem or solution I am missing here? Battery is new and there are no other electrical issues from what I can tell apart from a rear light fuse that went a while back (a different fuse box).

 

[Leo]

Could be a frayed wire somewhere causing a short. With the wiring running through the door hinge there will be movement and wear over the years.

 

[Pinoy adventure]

If it keeps blowing it will be the wiring.check all the cables for breaks or splits.

 

[bstop]

Try switching off the cabin lights permanently and see if the fuse blows. If it doesn't then the fault is in the cabin light circuit. If it blows with the cabin light permanently off try not operating the windows for a period. If the fuse then doesn't blow it's a window circuit fault. This might narrow down the fault. Something as simple as a dodgy bulb could be the cause.

 

[NoRegretsCoyote]

Try switching off the cabin lights permanently and see if the fuse blows.

Thanks, not sure if this is possible but will try.

Something as simple as a dodgy bulb could be the cause.

Very cheap in scheme of things to replace.

With the wiring running through the door hinge

Good idea I will check this as it should be accessible. I have previously taken out the control panel out of the door and no obvious problem there.

 

[bstop]

There is usually a switch on the cabin light. 3 position, permanently on, permanently off and on when door is opened.

 

[Baby boomer]

This needs to be found and fixed. There's an intermittent short circuit somewhere (probably a frayed wire as @Leo suggests) that's not going to go away by itself. Worst case scenario, electrical faults like that can start arcing, with sparks and it can start a fire.

There's a reason fuses were invented!

 

[Steven Barrett]

This needs to be found and fixed. There's an intermittent short circuit somewhere (probably a frayed wire as @Leo suggests) that's not going to go away by itself. Worst case scenario, electrical faults like that can start arcing, with sparks and it can start a fire.

There's a reason fuses were invented!

Was just about to post the same thing. Had a similar problem with my last car, although nowhere near as frequent. Mechanic found it easily enough and fixed it but said if I ignored it, there was a risk of causing a fire in the boot.

It's not a big job. the mechanic doesn't have to do a full diagnostics, they know where the issue is, they just need to find the faulty wire.

 

[bstop]

It's not a big job. the mechanic doesn't have to do a full diagnostics, they know where the issue is, they just need to find the faulty wire.

I wouldn't bet on that. Any fault that only happens intermittently can be extremely hard to locate. That's why I suggested some simple ways to try and narrow down the search area.

 

[RetirementPlan]

You'd probably be better with an auto-electrician rather than a mechanic. I have a number for a guy in south Dublin who sorted out a wiring problem that affected the boot lock for us some years back, if you want to message me. Very modest cost, and he was able to come to us and do the work on site.

 

[Baby boomer]

You'd probably be better with an auto-electrician rather than a mechanic. I have a number for a guy in south Dublin who sorted out a wiring problem that affected the boot lock for us some years back, if you want to message me. Very modest cost, and he was able to come to us and do the work on site.

That's a good point actually, a lot of mechanics are cagey around electrical stuff. But those who do go into auto-electrics tend to be very good at it.

 

[Leo]

I have a number for a guy in south Dublin who sorted out a wiring problem that affected the boot lock for us some years back, if you want to message me.

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