Rear Fog lights / Horn not working

For all those wiring gremlins we love, this is the place to discuss them.

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alangs1200
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Re: Rear Fog lights / Horn not working

Post by alangs1200 »

Thanks Tony. I know the horn was working as whilst fixing other stuff inside the car I managed to sound it a couple of times (usually due to grabbing the wheel to haul myself out of the footwell). It was only when I'd "finished" and decided to do that "let's just check that everything electric is now working" that it didn't want to play anymore. Fortunately the weather looks OK for tomorrow so I'll start by checking the earths on the switch and compressor and just double check that the green wire to the horn switch from the connector block under the steering column has power. Once I've done that then if it's still not working then I know I either have a problem with/at the switch or the compressor.

From what I read the compressor is accessed by removing the passenger side headlamp. I have yet to determine how I might access the switch but it can't be too hard .... can it?
1993 - parted with an Excel Celebration to make way for kids. 2020 - parted with the kids to make way for an Excel SA.

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Hawaiis0
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Re: Rear Fog lights / Horn not working

Post by Hawaiis0 »

alangs1200 wrote:
Tue Dec 29, 2020 16:57
know I have power to the relay and power on the Purple Black wire (at least as far as the connector block under the steering column) then next must be to check whether i have power on the purple/yellow wire to compressor. If I do then I either have a faulty switch, faulty compressor or a dodgy earth on one or both of those. I think!
Check the earth route through the horn button at the connector.
Prove by making a short to earth at the connector on the post relay PB supply, thus bypassing the horn switch function and connector. This will simulate a horn push and twinkle the horn.

A good continuity to earth through the horn push points to the PY supply line to horn compressor and horn via the Front Harness Connector (FHC). Did we confirm power at the PY pin on the relay base?
edit1
Or the relay is not switching of course.
edit2
Are the relays correctly positioned? 5 pin for the Horn, 4 pin for the HRS ! Are they transposed in error as next to each other?
Nothing is fool proof. Fools are clever!

alangs1200
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Re: Rear Fog lights / Horn not working

Post by alangs1200 »

Thanks to all, especially Hawaiis0 for the advice. All sorted.

Final part of the conundrum solved this morning when by bypassing the horn switch and getting a longed for "toot" it meant that the culprit for the horn was the switch. Popped this out of the steering wheel and did another bypass from from the power at the switch direct to earth for another "toot" meaning either the switch wasn't functioning or it wasn't earthing. Took it apart - nothing evidently wrong, but gave it a good clean, wire wool for the connections and a contact cleaner to follow, reassembled and all is now well. So, loads of headaches for two problems I'd assumed were related to me fixing the rheostat. Turns out one element (rear fogs) hadn't been working since I had the car due to swapped connector behind the dash and one was down to a fault that obviously manifested itself at the same time as I had the dash out to fix the rheostat - probably just a coincidence. Proves that the old adage about assumption is spot on - at least in my case!

Anyway, thanks to all the helpful suggestions here I've been able to work it through logically, identify and cure two faults at a total cost of zero!

You're an epic lot! Thanks & a happy new year.
1993 - parted with an Excel Celebration to make way for kids. 2020 - parted with the kids to make way for an Excel SA.

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Re: Rear Fog lights / Horn not working

Post by Hawaiis0 »

alangs1200 wrote:
Wed Dec 30, 2020 12:28

...... identify and cure two faults at a total cost of zero!
We haven't sent in the invoice yet. :wink:

Great to hear the successful outcome.

What's next?
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Re: Rear Fog lights / Horn not working

Post by alangs1200 »

What's next? Drive it!!

I have (almost) finished the job list I gave myself when I bought it in the summer. Aside from repainting the cam covers I'm all done! So, until something breaks ..... drive it!
1993 - parted with an Excel Celebration to make way for kids. 2020 - parted with the kids to make way for an Excel SA.

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Re: Rear Fog lights / Horn not working

Post by richardw »

Great result. Hawaiis0 (Stu) is the man!

We’re getting a very good number of SA owners on here. Mines an SA beneath the skin, and they are, in my opinion, a seriously underrated car.

Cheers, Richard
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Re: Rear Fog lights / Horn not working

Post by alangs1200 »

Indeed, very underrated. On the plus side I think my engine (original and now with 145,000 miles) is still smooth as silk, with solid oil pressure - something I’m sure is because the auto doesn’t rev as aggressively and/or autos aren’t bought by people that want to hit the red line everywhere! It’s also a doddle to drive.

But the 4 speed, widespread ratios do make it seem a bit dated. Our 2 daily drivers are both autos and have 7 and 8 speeds. Aside from wanting to retain the originality (my car is pretty original aside from the audio head unit) it would be nice if the engine could be mated to a 6,7 or even 8 speed modern auto!!
1993 - parted with an Excel Celebration to make way for kids. 2020 - parted with the kids to make way for an Excel SA.

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Re: Rear Fog lights / Horn not working

Post by Hawaiis0 »

alangs1200 wrote:
Wed Dec 30, 2020 21:26
It’s also a doddle to drive.

But the 4 speed, widespread ratios do make it seem a bit dated. Our 2 daily drivers are both autos and have 7 and 8 speeds. Aside from wanting to retain the originality (my car is pretty original aside from the audio head unit) it would be nice if the engine could be mated to a 6,7 or even 8 speed modern auto!!
I have mulled the GB swap to a 6 or 8 speed but (and I am not a mechanic) would the extra ratios mean constant gear changes?

The 4 we have suit the set up very well, and should you need to get into boy racer manual selection mode :D it will shift very well :wink:

Also, the cams come alive at 4000 revs, but you will be doing 100 mph in 4th by then, so I've been told - according to the specs. :shock:

The SA is a Gentleman's Cruiser with hidden potential.
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alangs1200
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Re: Rear Fog lights / Horn not working

Post by alangs1200 »

Doubtless it would mean more gear changes but a new generation box would change more smoothly. It would also kick down more easily (I know this is adjustable anyway) and it would also make it much easier to keep in the power band if that was what you wanted and it would probably make it more economical and give a quieter cruise as you'd be able to over gear it more in top.

All that said, nice as it would be, I don't think it's ever something I'll do - it's just nice to speculate sometimes!!
1993 - parted with an Excel Celebration to make way for kids. 2020 - parted with the kids to make way for an Excel SA.

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Re: Rear Fog lights / Horn not working

Post by TrevorK »

I think modern automatic transmissions are designed to work with electronic engine management systems, using ignition retard and drive-by-wire throttle to smooth the changes. With a carburetted Lotus, one would have to do some electronic work arounds to avoid it going into fault mode because it's not getting any replies from an engine ecu or ABS controller. etc.
What car is that?

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Re: Rear Fog lights / Horn not working

Post by Excel SA »

That's what I will end up with when it's finished some time in the future! Have kept all the Toyota electronics for the engine and gearbox - the new gearboxes do have computers to run things. Have gone with a 6-speed automatic mainly for lower revs at the legal speed limit.

Neil.

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