Headlight Changeover Relay 1972 US T

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kasbridge
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Headlight Changeover Relay 1972 US T

Post by kasbridge »

Hi,
Doing some fault finding as my dipped beam not working - I’ve got the SL-35 wiring diagram from Rennlist but before I start messing with the stalk (which I understand is the most likely culprit) which involves steering wheel removal I thought I’d test the relay shown as Headlight Changeover Relay as it’s cheap and hopefully easy to do.

So, does my car have one and if so where can I find it? It looks like it’s either going to be behind the instruments or somewhere in the trunk near the bulkhead.

Also I’ve been browsing the P reissued driver manuals but they don’t list the USA 911T - any ideas where I might source one?

Thanks as always, really enjoying getting to know the car!

Cheers,
Kevin
neilbardsley
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Re: Headlight Changeover Relay 1972 US T

Post by neilbardsley »

I guess the relays are either by the fuse board or in the bonnet behind the dash? Hopefully, someone you knows better will be along soon

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Lightweight_911
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Re: Headlight Changeover Relay 1972 US T

Post by Lightweight_911 »

kasbridge wrote: Thu Oct 23, 2025 2:46 pm
So, does my car have one and if so where can I find it? It looks like it’s either going to be behind the instruments or somewhere in the trunk near the bulkhead.
From memory these cars came from the Factory without any headlamp relay - hence the problems that can occur with the contacts in the column switch burning.


kasbridge wrote: Thu Oct 23, 2025 2:46 pm Also I’ve been browsing the P reissued driver manuals but they don’t list the USA 911T - any ideas where I might source one?
The crop up on ebay & Pelican fairly regularly ...


.
Andy

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- subtracting weight makes you faster everywhere”
kasbridge
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Re: Headlight Changeover Relay 1972 US T

Post by kasbridge »

Lightweight_911 wrote: Thu Oct 23, 2025 10:18 pm
kasbridge wrote: Thu Oct 23, 2025 2:46 pm
So, does my car have one and if so where can I find it? It looks like it’s either going to be behind the instruments or somewhere in the trunk near the bulkhead.
From memory these cars came from the Factory without any headlamp relay - hence the problems that can occur with the contacts in the column switch burning.


kasbridge wrote: Thu Oct 23, 2025 2:46 pm Also I’ve been browsing the P reissued driver manuals but they don’t list the USA 911T - any ideas where I might source one?
The crop up on ebay & Pelican fairly regularly ...


.
many thanks I missed these replies!
SeanP
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Re: Headlight Changeover Relay 1972 US T

Post by SeanP »

Headlight flasher relay is behind the fuel gauge. If you are looking for the headlight changeover relay that drops out the dipped beam when the main beam is activated
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Nine One One
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Re: Headlight Changeover Relay 1972 US T

Post by Nine One One »

This may help if you want to put a relay in, and also trouble shoot your wiring if dipped beam not working, dependant on the stalk itself, which may help identify what it is?

Although the is a later model, the basics will be the same, once you locate the correct wires in the fuse boxes.

https://www.youtube.com/watch?v=Rfzr_sPh4hw
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