[Lscole488]

My daughter has a 2007 TSX, it keeps blowing fuse 6 (interior light) in the interior fuse panel. I guess my initial thought is the door driver side door harness but not sure how to test it. Any thoughts or suggestions of probable cause?

 

[Litespeed08]

There are several ways to test the harness. The most complete way would be to access it and use a multimeter to test each point/wire for a ground. Or, you could open the door, replace the fuse and then close the door to see if that blows your fuse. This is very general and assumes that the door switch will open with the door and close when the door is shut. If the fuse blows then you know something in the door wiring or switch is bad.

I've also seen this happen when a bulb goes bad and one of the elements shorts to its casing. So it could just be a bad bulb.

 

[Lscole488]

Thanks for your input. Just one point on a bad bulb. When the fuse is replaced the dome light does work again. If the bulb was bad it would not light up again when the fuse is replaced. Would that be a correct assumption or could the light still function in that situation?

 

[Litespeed08]

Thanks for your input. Just one point on a bad bulb. When the fuse is replaced the dome light does work again. If the bulb was bad it would not light up again when the fuse is replaced. Would that be a correct assumption or could the light still function in that situation?

Yes and no. A single element bulb would not light up if shorted or open. A dual element bulb (brake light) would only work on the remaining good element most times. A weak element bulb may short but the output would be less than normal until it finally goes bad (open). And an LED is a whole other story.

If any bulb appears dim, replace it. If all bulbs seem normal then you probably have a bad/weak connection in your wiring or a faulty switch. This all assumes that there are no other electronic issues in your electrical system. If that is the case then you'll likely need an experienced electrical person to troubleshoot it.

 

[merlinj79]

Cheap and easy recon-by-fire...

Replace ALL interior bulbs, and the door switch. Might also be one of the other three door switches, so I'd try them next. The door switches (driver's anyway) get cycled a lot and they're attached to the big ground. Last would be the overhead dome light switch (it probably doesn't get cycled as much as the doors).

If that doesn't work, then look at the harness. Usually a harness problem in a modern car is going to be pin problems at the connector which would cause open circuits, not shorts. Modern harnesses rarely wear through to a short, they are routed carefully, tied down and wrapped in loom. That's why I'd look at the mechanical parts first.

 

[Lscole488]

Cheap and easy recon-by-fire...

Replace ALL interior bulbs, and the door switch. Might also be one of the other three door switches, so I'd try them next. The door switches (driver's anyway) get cycled a lot and they're attached to the big ground. Last would be the overhead dome light switch (it probably doesn't get cycled as much as the doors).

If that doesn't work, then look at the harness. Usually a harness problem in a modern car is going to be pin problems at the connector which would cause open circuits, not shorts. Modern harnesses rarely wear through to a short, they are routed carefully, tied down and wrapped in loom. That's why I'd look at the mechanical parts first.

 

[Lscole488]

Thanks for the input. Currently she has replaced the fuse again and told her to ope;and close the driver side door and see if the fuse would blow but seemed not to have an effect. She said the last time she changed it, it lasted a couple days. Told her to be aware to what point it blows again. Will look at it myself this weekend.

 

[Lscole488]

Well so far so good. The third fuse still remains unblown, so maybe just got a bad fuse.

 

[dogzop]

have you pulled out the interior lamp and seen if it stops blowing? the light could have shorted itself to ground. I believe that one also has the backup lamps on that circuit, see if they are out,if they are check for a shorted bulb tomzpot mobdro