Interior lights not switching off

[richhaynes]

Last week I had been out and about in my car with no issues. But then when I went to start the engine one time, the car sounded like it had a flat battery. I thought I needed a new battery but the battery tested good and the car started fine after a decent run.

Today came around and the car started normally this morning. But by this afternoon the car laboured when starting and the interior lights are failing to go off.

At first I thought I had a door switch issue but turning the switch to the off position resulted in the interior lights staying on. I checked for a short on the switch but that was fine. I checked all doors and boot again but they remained on.

A search pointed me to fuse 32 in the engine bay. This is apparently linked to one of the BCU modules and removing it did finally cut power to the interior lights. Unfortunately it's also cut power to my reverse light.

Can anyone provide any info on fuse 32 or the associated BCU? The location of the BCU module would be handy too.

If you need more info or have some diagnostic steps you want me to follow then let me know.

[Dave1419]

I would think that the battery is on its way out---how did you test it---the Insignia really needs a very good battery and if its dodgy it will be giving you all sorts of problems---have you any warning lights on the dash--and don't forget winter is coming and batteries tend to show problems about now-----Dave

[richhaynes]

The battery is reading 12.5V at the terminals. Charging at 14.4V. Tested with a multimeter.

My last siggy had a beast of a battery but this one is alot less powerful and I've not had any issues in the past 12 months with it. I have wanted to upgrade this battery but right now I just dont have the spare cash for a new battery let alone a better one.

When it first went dodgy, I had ran the car several times that day with no issues and then it acted dead straight away. It wasnt a gradual decline as you would expect. Since then its ran ok until today. It started fine when it was cool this morning but when it was warmer in the afternoon it struggled and the interior lights have played up since.

Since I removed that fuse, everything seems to be ok again. My thoughts is a faulty BCU causing some kind electrical fault in the system but I want to do some more digging first.