Lotus Elan and Lotus Elan Plus 2 Forums

My notes physically identifying the fascia switches have gone missing and I'm left with a box of unlabeled switches. If only Lotus would have put part numbers on them. When I disassembled the dash, those many years ago, I carefully put wrap around wire numbers on each wire as I removed them. Those numbers are still there but the notes Identifying the related switch terminals are also gone.

It's a simple matter to identify the functionality of each switch using a multi-meter and I've done that, grouped the switches based on the number of connections, rocker movement, and internal connections. Please see the attached excel file. Using the process of elimination and flat out wild ass guessing I?ve come up with the following. Please feel free to point out any glaring errors.

Switch #1 is the rear screen switch.
There?s only one momentary SPST switch. That should be the washer switch. Switch #2
There are two identical momentary DPDT switches that spring to center, the window switches, #3 and 4.
There is one other momentary DPDT switch that springs to center. That should be Park (side) Light Switch, #5.
Switch #6 should be the Interior/Panel light switch.
Switch #7 should be the Fan switch.
Switch #8 is the wipers.
The 3PDT switch should be the Hazard switch (probably not original), switch #9
Two SPST switches (switches #10 and 11) that are Fog and Spot light switches. These switches are still installed in the under-dash trim, so I know their ID.

Searches of the both the forum, the gallery, and the internet at large have come up with nothing. Can anyone point me to some documentation that will allow me to relate the standard wiring to the switch terminal numbers. The wiring diagram is not much help without the terminal numbers denoted for most switches other than SPST.
Why they thought they were needed for relays, down to the flasher relays and not switches is anybody?s guess.
Any and all help appreciated?

Edit: Posted updated xls attachment with corrections. Hazard switch is still up in the air. My switch may be bad.

2nd Edit: The above is almost total rubbish. Several switches were intermittent do to not being used in thirty plus years and provided bad readings with the ohm meter. Please see the post dated 2/11/2019 for the correct spreadsheet and switch identification.

Bud, take a look at this similar spreadsheet Gerry Minor did up to compare. Unfortunately I can?t view the sheet correctly right now on my iPad, but I believe it was clear enough when it opened correctly on my computer. If I recall correctly he put each switch on a separate tab. He alludes to terminal numbers on the actual switch body, but I had never noticed them.

lotus-electrical-f38/dashboard-switches-s130-rewiring-info-t21224.html#p125554

Not sure if it is an issue for you, but I believe the (perhaps earlier) Federal Non S diagram that my car follows shows the switch terminals in the diagram; not numbered but shows physical layout. It is the drawing that is not laid out as a schematic; rather it shows the physical location of the loom runs and highlights each wire by a number code rather than letters for a colour code. Might help with your connections? Do you have that diagram or is it the one you are using? I can probably post a copy if needed.

HTH

Stu

Bud, I happen to have my dash out at the moment. If you like I can post a picture of the connections of each switch. I think 90% are the same between my federal Sprint & your federal +2S

I'll second Stu's recommendation of that drawing.

Also my dashboard is still out but ready to go back in and that was going to be this weekend's project, so let me know.

Thank you all!

Stu- Not sure how I missed that excel spreadsheet that you referenced. I'll be able to use that along with the diagram for the S130 to see how they relate and proceed from there. I do have that layout drawing. I'll check that out as well.

the Veg- A couple of pics of the back of your dash would be helpful if it's not a bother. I've been following your posts on your trouble shooting it after getting it back together. I'm aware that it's an non S car but I don't think that will be a problem. The year is right and I don't think that there are much, if any differences, in the switch wiring between the S and non S.

Phil- I'll let you know if your Sprint pics will help after I sort through the other info referenced. Of course those photos may help someone with a Fed Sprint that may stumble on this thread.

Again, thank you.

Here are the switches:

Let me know if you'd like close-ups of the relevant parts of that drawing. I tried posting them but for some reason the files are too large, despite being the same camera I used for the switch pics. I can resize them or put them in an online gallery if need be. The is drawing g Des show the physical configuration and connection of the different terminals on the switches.

After cleaning all of my switches with contact cleaner I was able to trace the internal connections for each switch more accurately than the first time around. I found some missing connections caused by them having dirty contacts. Looking at the outside surfaces of the switches I can tell how they were installed in the dash; clean on top. Two get installed upside down.

Most, but not all switches are shown on the wiring diagrams with the contacts oriented correctly. At least one is shown upside down and one as a mirror image. Using the references suggested and other posts on specific circuit operation, I think I'll soon have it dialed.

I've attached another updated switch diagram. When I'm done and everything checks out I'll update it if there any changes.

Bud, great ou will be updating your spreadsheet and consolidating some Plus 2 information.

Here is a link to the Plus 2 Federal Wiring Diagram I referenced above (coincidentally posted for another member).

lotus-electrical-f38/wiring-diagram-for-elan-federal-t43741.html

Although maybe not directly applicable to your model, it attempts to show the switch connections in the diagram. As you point out above, the usual cautions apply that sometimes the connectors or switches may be shown upside down or unexpectedly as a mirror image; sort of not consistent what side or view the components are drawn from. Anyway, thought even with its limitations it might help someone out in the future to know what the heck we were talking about.

All the best with the project and keep us posted.

Now that I have figured out how to print the various diagrams to individual PDF files that are small enough to post I may add the whole wack for the Plus 2 here for future reference.

Stu

Here are three drawings that were included in the front portion of my parts manual in a section called ?Service Notes?. The drawings don?t seem to reference a particular model, but may be of assistance in establishing the general dash wire connections.

HTH

Stu

Thanks Stu, those service notes are quite handy. Too bad they didn't think them relevant in later years/variants. A lot of the info relates to what I've found.

The initial post above is almost total rubbish. Several switches were intermittent do to not being used in thirty plus years and provided bad readings with the ohm meter. I was able to disassemble and clean the offending switches and used spray contact cleaner on the rest. Please see the corrected spreadsheet and switch identification, attached. I think that is the final version.

I don't think there's a better way to familiarize yourself with how everything should work, electrically at least, than pouring over the wiring diagrams and the switch related posts to the forum. By the time I'm finished with the new harness I think I'll have it pretty well figured out.

Excellent Bud. Thanks for posting. That will be handy for others.

Stu