Lotus Elan and Lotus Elan Plus 2 Forums

The plot thickens.

According to the S wiring diagram in the Brooklands workshop manual (p. 159) it says the lighting circuit already has relays... although they aren't where it says they are. What's going on?

JonB wrote:The plot thickens.

According to the S wiring diagram in the Brooklands workshop manual (p. 159) it says the lighting circuit already has relays... although they aren't where it says they are. What's going on?

"A serious retrograde step with the 130 was the replacement of the original (S) 12 fuse with the central dash 4 fuse. Presumably for cost. "

The relays got the chop at the same "upgrade". Look for a specific S130 diagram not just the earlier S.

The S-130 diagram also has the benefit of being better drawn and therefore easier to read.

I went in through the front grill, mounting the relays on the front of the wheel arch. Access was ok although you can only really get one arm in at a time!

Robbie

JonB wrote:The plot thickens.

According to the S wiring diagram in the Brooklands workshop manual (p. 159) it says the lighting circuit already has relays... although they aren't where it says they are. What's going on?

My S3 has headlamp relays, one for main and one for dipped, but they are not wired in the logical manner (to reduce the current through the steering column & dashboard switches), instead they merely serve to turn the lights off when the pods are down, the pod microswitches release the relay..

One day I'm going to rewire them sensibly.

The earlier plus 2s probably had the same weird logic and so the relays were not really necessary, but I did not know (until reading the above messages) that they had removed them.

JonB wrote:Have ordered two relays (one for main, one for dip) with inbuilt 30A fuses, plus some 20A cable and some spade connectors.

With 30A fuses and 20A wire, the wire becomes the fuse in a short circuit situation.

Bud English wrote:

JonB wrote:Have ordered two relays (one for main, one for dip) with inbuilt 30A fuses, plus some 20A cable and some spade connectors.

With 30A fuses and 20A wire, the wire becomes the fuse in a short circuit situation.

Got spot.. They are modern blade fuses and I had planned to change them. I wanted to be sure the relay was higher rated, that's why I bought these units.

So, it seems like I have something that is quite original. 20A through the light switches, imagine that. It's like something out of the Dark Ages.

vincereynard wrote:"A serious retrograde step with the 130 was the replacement of the original (S) 12 fuse with the central dash 4 fuse. Presumably for cost. "

The relays got the chop at the same "upgrade". Look for a specific S130 diagram not just the earlier S.

That diagram isn't in the Brooklands manual. It only goes as far as the Plus 2S. Has anyone got a scan, or a link to a scan of this wiring diagram?

Welcome to the world of Lotus electrics



HTH,

Regards, Tim

JonB wrote:So, it seems like I have something that is quite original. 20A through the light switches, imagine that. It's like something out of the Dark Ages.

Ah, the awakening of wisdom Grasshopper!

It's a 60's car and, to be frank, built with cost a greater priority than quality. Probably it's contempories were
much the same. Have a look at the diagram for a Triumph of the same vintage.

On the other hand it is simple and has worked, after a fashion, for nigh on 50 years.

Out of interest what is the wire circled for? It is unconnected in mine and seem to make no difference.


Vince

vincereynard wrote:Out of interest what is the wire circled for? It is unconnected in mine and seem to make no difference.

ScreenHunter_301 Nov. 20 10.30.jpg

Vince

Pretty sure it's for the headlight flash system, if your dip switch has that function. On my +2, with lights off, if I pull the stalk, if you'll forgive the expression , the lights pop up with main beam lit, then return when the stalk is released. With lights on dipped beam, a pull on the stalk will flash main beam, as per modern things. My Elan doesn't have this function, something I'd like to remedy if I can ever find another dip switch with the flash facility.

Regards, Tim

Orsom Weels wrote:Welcome to the world of Lotus electrics

Wiring diagram_ElanPlus2S130.pdf

HTH,
Regards, Tim

Thanks, Tim - you're a life saver. Possibly literally, in my case. I was looking around it and there are no relays ANYWHERE. Oh, apart from the horn.. bizarre... Not the lights, we knew that - but the window winder motors? No wonder they are sluggish. Guess I will be fitting a shed load of relays. Lights, window winders at least, then rear demister and wiper motor to help spare the switch contacts.

My lights have the "flash" function but only when the pods are already up. I'll be looking at that circuit as I think it'd be cool to get it working.

JonB wrote:Other thing I noticed - when the lights pop up, they pause at about 80% for a second or so, then come up fully. They also come up of their own accord when it's cold (according to the PO). Most odd.

Answering myself here - feel free to challenge.

On the subject of the "pause", I discovered that the driver's side pod is rubbing as it comes up. This is probably what causes it to stop momentarily. The pod's not quite aligned in its little bay and it rattles slightly, there is play in the offside pin.

Regarding the lights popping up overnight, it seems this is a side effect of the "failsafe" feature. They are sprung to go up, and the vacuum holds them down (for ~12 hours according to the manual). I may have a slight leak but I doubt it; the Spyder chassis cross rail is solid. Maybe at the valve... any other S130 owners notice this happening to their lights?

Orsom Weels wrote:Pretty sure it's for the headlight flash system, if your dip switch has that function. On my +2, with lights off, if I pull the stalk, if you'll forgive the expression , the lights pop up with main beam lit, then return when the stalk is released.
Regards, Tim

Thanks Tim - of course it is! Presumably disconnected when the electric lift stuff was added.

When I find some good spot light LEDs I'll use it to trip a relay and flash the spots. It may be a usefull backup in case the main lights fail!

If the dip stalk is in high beam position only, pulling back will action solenoid and flash headlamps.
Alan

Jon, you're very welcome.
It's almost certainly a vacuum leak somewhere causing your lights to creep up after a while, & it's about as common as sand in a desert. It's very rare to find a failsafe equipped car that will keep it's lights down for more than a day or so, & one of the reasons so many get converted to electric lift. I did mine last winter using a single Lotus Excel motor, which is basically Toyota MR2 or Celica, I believe. Works a treat, wish I'd done it years ago.
Vince, I used the original electric supply to the old vacuum solenoid valve to trigger the relay for the motor, & hence the flash still works to pop the lights up & flash them.
Alan, Mine doesn't do that, if the lights are on & high beam selected, pulling the stalk has no effect, any other scenario, it lights main beam until the stalk is released.

Regards, Tim