Is my Sprint ignition switch faulty?
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I’m nearing the end of my Sprint’s rebuild.
The ignition switch is column-mounted and is a Lucas 157SA, fitted on an earlier owner’s rebuild in 1988.
From what I understand, it should work as follows:
Position 0 - key in slot
Position 1 - supply to “accessories” (radio, cigarette lighter, horns)
Position 2 - supply to ignition and all other electrics
Position 3 - spring-loaded supply to starter via solenoid
My switch however does NOTHING in position 1.
I’ve checked the switch wiring and it’s correct per the wiring diagram (although the switch terminals are numbered 1,2,3,5 rather than 1,2,3,4 on the diagram).
Terminal 5 (otherwise 4) has the white/purple wire to the fuse box, which then has purple wires to the “accessories”, but doesn’t become live in position 1, only in position 2.
So, I’d appreciate some advice as to whether the switch is faulty, or are they all like that?
The ignition switch is column-mounted and is a Lucas 157SA, fitted on an earlier owner’s rebuild in 1988.
From what I understand, it should work as follows:
Position 0 - key in slot
Position 1 - supply to “accessories” (radio, cigarette lighter, horns)
Position 2 - supply to ignition and all other electrics
Position 3 - spring-loaded supply to starter via solenoid
My switch however does NOTHING in position 1.
I’ve checked the switch wiring and it’s correct per the wiring diagram (although the switch terminals are numbered 1,2,3,5 rather than 1,2,3,4 on the diagram).
Terminal 5 (otherwise 4) has the white/purple wire to the fuse box, which then has purple wires to the “accessories”, but doesn’t become live in position 1, only in position 2.
So, I’d appreciate some advice as to whether the switch is faulty, or are they all like that?
- Lotusian
- Second Gear
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- Joined: 27 Nov 2016
See https://lotuselan.net/forums/viewtopic.php?f=38&t=24891
Will have to think about / check your position 1 issue, though I think I noticed the accesory position not working on both my old & new 157SA switches. I still have the old switch, so can check how it is wired internally.
Will have to think about / check your position 1 issue, though I think I noticed the accesory position not working on both my old & new 157SA switches. I still have the old switch, so can check how it is wired internally.
Phil Harrison
1972 Elan Sprint 0260K
1972 Elan Sprint 0260K
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pharriso - Coveted Fifth Gear
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Craven wrote:Any help,
viewtopic.php?f=14&t=24891&start=
You posted another link to exactly the same thread as I did
Phil Harrison
1972 Elan Sprint 0260K
1972 Elan Sprint 0260K
-
pharriso - Coveted Fifth Gear
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- Joined: 15 Sep 2010
It seems possible that when the switch was mounted to the key barrel the rotating contact was in the wrong position.
There is also this link https://majcd213.blogspot.com/2016/11/i ... witch.html
Sorry can’t help further.
There is also this link https://majcd213.blogspot.com/2016/11/i ... witch.html
Sorry can’t help further.
- Craven
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Lotusian wrote:Pharriso and Craven
.....
Could you please advise what yours actually do?
Ian
Went to see my car in storage yesterday & Yes the accesory position 1 works as expected, with Power to the Radio, Horn & Cigar lighter.
This topic piqued my interest, as I still have my old SA157 in pieces I thought I would see exactly how the switch worked internally. So here we go:
This is the molding with all of the contacts mounted. I have indicated the contact number on the sheet of paper & also marked the extent of that contact around the perimeter of the plate with black marker:
Now I place the contact piece into the assembly & show it in the postion (Position 0) that the key is inserted in or out:
Now let's rotate the contact to Position 1:
Let's rotate to Position 2:
One last turn to Position 3:
The connectivity can be summarized below:
This is completely different from the Dash mounted ignition switch (SA147) where power is supplied on Terminal 1 & connects as follows:
Note also on the SA147 switch that the accesory position is anti-clockwise from the Key insertion position, wheras Run & start are clockwise from the key insertion position.
Phil Harrison
1972 Elan Sprint 0260K
1972 Elan Sprint 0260K
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pharriso - Coveted Fifth Gear
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Pharriso and Craven
Thanks for all your help, as a result of which I have determined that, contrary to what I said earlier, my switch was wired incorrectly - terminals 2 and 3 were transposed. Having put this right, all now functions correctly.
Thanks a lot.
Ian
Thanks for all your help, as a result of which I have determined that, contrary to what I said earlier, my switch was wired incorrectly - terminals 2 and 3 were transposed. Having put this right, all now functions correctly.
Thanks a lot.
Ian
- Lotusian
- Second Gear
- Posts: 142
- Joined: 27 Nov 2016
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