Lotus Elan and Lotus Elan Plus 2 Forums

I am now at the point of trying to make sense of the messy wiring of my 130 S and after replacing the dash I am struggling to understand how the side lights and headlights should operate.
I have an early 130 S that has the fuses and relays under the bonnet and the ashtrtay in the 6 dial dash
I have 7 of the 9 rocker switches operating but I have two that I am not sure about, one is a two position switch and the other is a momentary switch the same as the ones that operate the windows
I had assumed that the two position switch was side lights on and then head lights on but it seems not

Can the side lights operate with the headlamp pods closed ?
Do the instrument lights come on with the side lights ?
I am using motors to lift the pods and this works well
Should say that when I got the car all the lights were removed and the cables had been chopped and most of the connections were terminal block

Not sure about an S130, but on an Elan the sidelights definitely work with the headlight pods down. They are needed as parking lights, which were obligatory in the Elan era.

For the same reason, though the panel lights come on with the sidelights, there is an extra switch to turn the panel lights off when the sidelights are on, this saves battery power when parked.

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But you will need to list what you have done to work out what you are missing.

billwill wrote:the panel lights come on with the sidelights, there is an extra switch to turn the panel lights off when the sidelights are on.

The way my car was wired from the factory, the panel (instrument) lights did not come on with the side lights. The panel switch did turn the instrument lights on, however that was the only way one could turn them on. The idea of pulling the headlight knob, flipping the side light/tail light switch, and then flipping the panel light switch every time I wanted to drive at night seemed a bit much, especially considering the fact that the panel switch was so far away from the other two. I re-wired the panel (instrument) lights to come on with the side lights and tail lights and I replaced the panel switch with a momentary switch (windscreen washer switch) to trigger the transmitter for my garage door opener which is wired into the car. The transmitter doesn't seem to mind 12V going through it and I never have to worry about the 9V battery wearing out.

I'm rewiring my +2S 130 which has the center fuses in the dash and thermal cut outs in lieu of relays but as I looked at the wiring diagrams they all seem to be very accurate and certainly the one I'm using for my federal +2 is precise. It does sound like maybe the momentary switch is for your washer squirter and the other one is perhaps for the panel lights. On mine a turn of the headlight knob runs the marker lights and then a pull out activates the vacuum release so the lights pop up (federal) And then activation of the dash switch turns on the panel lights. If you leave the panel light switch on so that it is activated all the time, then the panel lights are always coming on when you turn on the headlights but off automatically when no lights are on. Gordon Sauer

There is a Plus 2 Federal variant that uses a momentary switch and a relay for the side lights. My car is/was set up this way. To check for this variant, is/was there a small rectangular relay located on the heater box (right side IIRC on my LHD Federal)? I have posted a wiring diagram and explanation of this setup and can dig it out for you if req'd. It is kind of a quirky circuit that uses the relay to 'latch' the circuit in the on position, and the momentary off position 'unlatches' the relay. The relay is not used to switch the high draw main circuit like headlamps, horn, cooling fan, etc.

My flat rocker momentary switch is located right next to the knob for the headlamps on the lower switch row. At least on my car, this setup has the two microswitches located on a bracket on the headlamp vacuum switch. I can't recall if the actual momentary rocker switch is identical to the window switch, squirter switch, or both, but in my Workshop Manual it has different terminal layout (three terminals, two at top and one at the middle side).

The way this type operates is the side lights come on with the headlights, or they can be put on independent of the headlamps. The weird part is when the headlamps are turned off, the side lights stay on; one has to operate the momentary switch to turn them off.

As described above, there is a second rocker switch to turn the panel lights on and off; the side lights have to be on for this switch to see power though. This rocker is a three position affair; (1) off, (2) panel lights on, (3) panel lights & interior lights on (switched to ground, completely separate circuit).

Hope this is not too confusing, but this was the stock configuration on some of the Federal Plus 2's (Headlamp Failsafe System). For reference, my car is 50/2181, and it has flat switches with only four minor gauges and the two fuse setup (since upgraded). From previous threads, it seems there were several versions of the headlamp & side light circuits, and mine might have been only on earlier Federal cars? My Workshop Manual indicates the Headlamp Failsafe System was introduced on Federal cars after 50/1174.

Here is a link to where I posted the circuit. Note the OP had a different setup.

lotus-electrical-f38/side-lights-t17589.html

HTH

Thanks for your replies, I think I may have the momentary switch and relay arrangement !
I will have some time tomorrow to investigate further

The circuit is here in schematic form and easier to see how it works. Mike



lotus-electrical-f38/side-light-latch-circuit-t22484.html?hilit=plus%202%20side%20lights#p148515

Sam tex

PM me and I should be able to scan you a wiring diagram I will need year and model

Mike, what year / model do you have, and are they Fail Safe headlamps? I was not sure if some of the UK cars used this arrangement or if unique to Federal cars.

I could not follow the various Plus 2S wiring diagrams in my manual, but understand your schematic OK. The Federal diagram for my car in the Manual is more a layout type diagram than a pure schematic so it was tricky to figure the circuit out. Anyway, with both diagrams it should be OK for Sam Tex.

Stu

Stu,
Mine is a 1970 Plus 2S with non fail safe lights (2 Vac pods) with relays and fuse boxes under the bonnet. The circuit I posted works for that and is based upon a single micro sw under the LH headlamp pod. Activation of the vac s/w causes the side lights to latch on via activation of said micro switch.

The circuit in the manual is not very clear as I needed to work out which was the common on the switch. I am electrical (call me thick) but it is not clear in the diagram without some thinking, logic assuming and following the circuit.

I hate those fail safe ones where you return afer a while and it has become a frog!
Yes you can chase down all the vac leaks but you can live with some slight ones on the non fail safe.
Mike

Sam tex

Hi
As I have been having troubles using the forum I am not sure you have received my response to your request for help. If you PM again I have the wiring drawings for your car.
Send me your e mail as the drawings will better this way

billwill wrote:Not sure about an S130, but on an Elan the sidelights definitely work with the headlight pods down. They are needed as parking lights, which were obligatory in the Elan era.

They are position markers and are obligatory. They need to work independently of the headlights.