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Sudden loss of dipped headlights

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Recently had heater matrix etc done.

However, there was an issue with no side lights but did have headlights and main beam. A body control unit was replaced.

Last night lost dipped headlights on the way home - had to complete the journey with sides and front fogs 馃槓馃か

Also cabin fan is very intermittent - even a door closing can cause it to go off or come back on.

Any ideas....?
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Both lamps blew at the same time? It happens.
Will certainly check the bulbs.... Was running osram night breakers - would prefer not to have to buy two of these again 馃ぃ
Yeah they are good/pricey but the downside is they do have less lifespan.
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The light switch commands the lights on, the stalk controls dip or main. For dipped beam, the BCM drives the relay R1 in the aux relay box under the bonnet, this feeds a fuse for each headlight. For main beam, the stalk switch directly drives relay R4 in the aux really box which in turn feeds a fuse for each main beam.

If you can switch on the front fogs, then the BCM is getting a 'headlight on' signal I think, so that suggests either the relay R1, both fuses, both bulbs or a common wiring fault. Given the other symptoms, a common wiring fault might be to blame.
Thanks guys.... Nuts and bolts are so much simpler in my wee northern Irish mind 馃馃ぃ
Will certainly check the bulbs.... Was running osram night breakers - would prefer not to have to buy two of these again 馃ぃ
Lidl stock +100% brighter H7s every now and then.
Priced at 鈧6.99 a pair down south.
They're decent enough IMO
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Lidl stock +100% brighter H7s every now and then.
Priced at 鈧6.99 a pair down south.
They're decent enough IMO
Alas it's Xenons....
The light switch commands the lights on, the stalk controls dip or main. For dipped beam, the BCM drives the relay R1 in the aux relay box under the bonnet, this feeds a fuse for each headlight. For main beam, the stalk switch directly drives relay R4 in the aux really box which in turn feeds a fuse for each main beam.

If you can switch on the front fogs, then the BCM is getting a 'headlight on' signal I think, so that suggests either the relay R1, both fuses, both bulbs or a common wiring fault. Given the other symptoms, a common wiring fault might be to blame.
Is the system different to the 156 then? I remember with both of mine I could run front fogs with just sidelights on, it was only the rear fog light that would only work with headlights on.
Is the system different to the 156 then? I remember with both of mine I could run front fogs with just sidelights on, it was only the rear fog light that would only work with headlights on.
You could well be right about that, hence my 鈥淚 think鈥 caveat!
So the mystery deepens.....

Auto Spark yesterday replaced the dipped headlight relay and we had lights. Wahoo.

However, after he left I noticed the cabin fan wasn't working. So a little wire wiggle here and there between the connector to the cabin fan and the fan motor housing and the fan springs to life.

However, now I have no dipped lights again!
There is 11.8v at the relay socket....

Fan is intermittent sometimes works and sometimes starts but then cuts out almost immediately....

Confused.....
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Could it be one or two burned fuses or a bad battery?
Could it be one or two burned fuses or a bad battery?
New yuasa battery put on....

Yup fuses checked/ replaced/swapped....

Def a mystery.....

Increasingly thinking body control module.

It was replaced to address the no side lights, so maybe purely coincidentally the used replacement has given up the ghost.....
The heater fan is controlled by the climate module so no direct connection with the BCM.

A common issue with the heater fan is the dedicated 30A (I think) fuse that feeds it - the fuse holder tends to cook over the years.

I suspect this will need some thorough and careful diagnostic testing鈥.and that鈥檚 going to be expensive unless you can DIY. Firing the parts canon isn鈥檛 likely to sort it I suspect.
The heater fan is controlled by the climate module so no direct connection with the BCM.

A common issue with the heater fan is the dedicated 30A (I think) fuse that feeds it - the fuse holder tends to cook over the years.

I suspect this will need some thorough and careful diagnostic testing鈥.and that鈥檚 going to be expensive unless you can DIY. Firing the parts canon isn鈥檛 likely to sort it I suspect.
Yeah the 30A fuse cooked as I watched several years ago... Smoke was a pretty clear indicator....

The bushes on the motor have also been suggested..... So will aim to get the aircon degassed etc and take it out to check
Yeah the 30A fuse cooked as I watched several years ago... Smoke was a pretty clear indicator....

The bushes on the motor have also been suggested..... So will aim to get the aircon degassed etc and take it out to check
Just to update this.... Replaced the Body Control Module and normal headlight function has been restored.....

Perhaps simply a coincidence that the replacement BCM worked for a few weeks then stopped with different behaviour to the original one.
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