Headlight Fault Finding (brightness)

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svenedin
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Headlight Fault Finding (brightness)

Post by svenedin »

As well all know, the performance of our standard headlights are not exactly awe inspiring.

I just thought I'd share a few things that I have discovered recently. Probably most people would know this but it was new to me even as a very long term owner.

My headlights have never been great. As a 1969 car it had sealed beam headlights but this applies to all types and series of Minors.

I had a new loom a couple of years ago and the headlight brightness was improved by this. As well as the new main loom there were also new connectors ("pigtails") to the headlights and new earthing points to the inner wings. However, the improvement wasn't as good as I had hoped and I eventually realised that the headlight switch in the dashboard was the original, very old and dirty. I replaced this and the brightness of the lamps improved a bit more.

Then I had a lot of ignition problems which I eventually traced to the ignition switch. I suddenly realised that the headlight dip switch on the floor was the original. Sitting in a very mucky place and very dirty inside. I had never really considered how the switch works. I had not realised that it is actually a changeover switch. We all know it switches between dipped and main beam but it had never occurred to me that the dipped circuit is connected by this switch all the time that dipped lights are in use (most of the time). I changed the switch and now the headlights are as good as they will get in standard configuration.

Summary: don't forget the dip switch is in circuit all the time. Everything else can be perfect but poor contact either internally or in the connections to this switch will undo your improvements.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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svenedin
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Re: Headlight Fault Finding (brightness)

Post by svenedin »

My lovely dip switch. Yuk!

Stephen

IMG_3456.jpeg
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1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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geoberni
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Re: Headlight Fault Finding (brightness)

Post by geoberni »

Basil being much older than your car, his Dip Switch is connected on the underside of the floor..... :o

During Covid I discovered the Dip Switch was intermittent, sometimes killing the headlights completely and needing a couple of extra stamps on the switch to get them back on, so I took it apart as the early switch is twice the cost of the latter one at around £33. :roll:

I don't know if the latter design can be overhauled in the same manner, but I made a short video of the work.
I think the latter one is just kept together by the casing edge being bent over.

https://youtu.be/jCTcLwJVuDs
Basil the 1955 series II

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svenedin
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Re: Headlight Fault Finding (brightness)

Post by svenedin »

Nice video Berni.

Yes, the later switch has the metal case folded over the plastic so could be opened quite easily. The "button" is also held on by metal tabs.

I wonder whether these switches were ever fitted with a rubber cover? It would have made sense if they were.

Stephen


IMG_3458.jpeg
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IMG_3457.jpeg
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1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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geoberni
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Re: Headlight Fault Finding (brightness)

Post by geoberni »

svenedin wrote: Thu Jun 11, 2026 1:39 pm Nice video Berni.

Yes, the later switch has the metal case folded over the plastic so could be opened quite easily. The "button" is also held on by metal tabs.

I wonder whether these switches were ever fitted with a rubber cover? It would have made sense if they were.

Stephen
IMG_3458.jpegIMG_3457.jpeg
I've not seen anything in the original parts lists. :-?
Basil the 1955 series II

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svenedin
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Re: Headlight Fault Finding (brightness)

Post by svenedin »

geoberni wrote: Thu Jun 11, 2026 3:54 pm
svenedin wrote: Thu Jun 11, 2026 1:39 pm Nice video Berni.

Yes, the later switch has the metal case folded over the plastic so could be opened quite easily. The "button" is also held on by metal tabs.

I wonder whether these switches were ever fitted with a rubber cover? It would have made sense if they were.

Stephen
IMG_3458.jpegIMG_3457.jpeg
I've not seen anything in the original parts lists. :-?
Neither have I but perhaps such a thing existed in other cars?

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Bill_qaz
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Re: Headlight Fault Finding (brightness)

Post by Bill_qaz »

svenedin wrote: Thu Jun 11, 2026 4:08 pm
geoberni wrote: Thu Jun 11, 2026 3:54 pm
svenedin wrote: Thu Jun 11, 2026 1:39 pm Nice video Berni.

Yes, the later switch has the metal case folded over the plastic so could be opened quite easily. The "button" is also held on by metal tabs.

I wonder whether these switches were ever fitted with a rubber cover? It would have made sense if they were.

Stephen
IMG_3458.jpegIMG_3457.jpeg
I've not seen anything in the original parts lists. :-?
Neither have I but perhaps such a thing existed in other cars?

Stephen
Maybe something like this?
442CAP: Rubber cap for floor mounted dip switch 442 (31284) for Classic & Vintage Cars | Vintage Supplies | Classic Bulbs https://share.google/2j68XZNYx4iOOIykE
Regards Bill
Bawdy2
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Re: Headlight Fault Finding (brightness)

Post by Bawdy2 »

svenedin wrote: Thu Jun 11, 2026 11:21 am As well all know, the performance of our standard headlights are not exactly awe inspiring.

I just thought I'd share a few things that I have discovered recently. Probably most people would know this but it was new to me even as a very long term owner.

My headlights have never been great. As a 1969 car it had sealed beam headlights but this applies to all types and series of Minors.

I had a new loom a couple of years ago and the headlight brightness was improved by this. As well as the new main loom there were also new connectors ("pigtails") to the headlights and new earthing points to the inner wings. However, the improvement wasn't as good as I had hoped and I eventually realised that the headlight switch in the dashboard was the original, very old and dirty. I replaced this and the brightness of the lamps improved a bit more.

Then I had a lot of ignition problems which I eventually traced to the ignition switch. I suddenly realised that the headlight dip switch on the floor was the original. Sitting in a very mucky place and very dirty inside. I had never really considered how the switch works. I had not realised that it is actually a changeover switch. We all know it switches between dipped and main beam but it had never occurred to me that the dipped circuit is connected by this switch all the time that dipped lights are in use (most of the time). I changed the switch and now the headlights are as good as they will get in standard configuration.

Summary: don't forget the dip switch is in circuit all the time. Everything else can be perfect but poor contact either internally or in the connections to this switch will undo your improvements.

Stephen
That’s very helpful thank you for sharing
Stewart
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