What does an OEM Lotus Plus 2 do?

[mjbeanie]

I have been sort of successful wiring the flasher circuit using the 6 pin flasher switch from RD Enterprises. I have an August 71 build with 3 fuse boxes. I can get all corners of the car to blink when activating the Flasher switch. However I am not sure it is 100% correct.

My question is a simple one on intended OEM operation. I am not sure this is the same as the factory..

With the parking/ running lights OFF: and Hazard ON: The taillights and front indicator lights blink from
OFF to ALL Brightly ON.

With the parking/running lights ON, and Hazard ON: The taillights and front indicator lights blink from
"Dim ON", to "BRIGHT On". (Not OFF to Bright ON). Is this how it is supposed to be?

Thanks-Just want to know if I mucked up something or is this ok? Appreciate the insight.

(If you ever want to age quickly- suggest rewire a Lotus Plus 2 project...)
Cheers
MIke

[Sadbrewer]

[quote="mjbeanie"

(If you ever want to age quickly- suggest rewire a Lotus Plus 2 project...)
Cheers
MIke[/quote]

Mike, I can't assist with the problem, but you really do need a competent auto electrician to do the job....this is where so many of the Lucas Prince of Darkness stories come from...(with all due respect to you Mike, and I accept we all like to do a bit ourselves and save money).We owner/amateurs butchering/modifying wiring systems without knowing the consequences are the biggest danger to the long term good health of the car. ..add a few owners over the years adding their own creative wiring and the system is doing things never intended...and very often doing them wrong. We were in the trade for over 40 years, my old man could tackle any electrics problem, but the vast bulk were relatively simple if the car was unmodified, the problems came when the owner or his equally unskilled buddy had decided to tinker first.
I would bite the bullet and find a competent pro, he may well spot other problems.
Andy

[HCA]

With the parking/running lights ON, and Hazard ON: The taillights and front indicator lights blink from
"Dim ON", to "BRIGHT On". (Not OFF to Bright ON). Is this how it is supposed to be?

No, it is not! There is meant to be a clear break between 'lights on' and lights off'.

Your car has been changed on its importation to function the crazy way that American cars seem to cling to - using one red light to incorporate brake, side and indicator lights. This requires an electronic box with several cross overs inside that your rear lights connect to. I have never seen one of these boxes, nor have I seen any wiring diagrams, so cannot help out immediately, other than advise you to go to an auto electrician who understands the working of the box (you might need a wiring diagram - maybe RD can help..)

Or, take the car back to how it meant to be...

[Craven]

HCA,
It’s a Lucas R 10. 2 change over relays in one can cleaver piece of relay logic.

[HCA]

!!
Thanks Craven! I shall print it off and file it! I knew it had to be something like this, but never cared to explore!

I could never get to grips why they want to complicate things more than they already are.

[gjz30075]

Is a Lucas R 10 the same as a DB10 (Lucas)? If so, that's most likely your problem. They are
readily available through Moss motors and other vendors.

[Craven]

Looks like DB 10 is a more common designation and available just the price is a bit scary.
Can be replicated with cheap standard relays.

[mjbeanie]

I appreciate the responses. They will be carefully considered. I have been rebuilding this car from the ground up and it is going well. I have a reasonable skill set as an engineer to continue the troubleshooting. At this point, I don't intend to farm it out. I like the feeling of victory after a challenging task.

This car was just a carcass. I have wired the whole car with a suite of 3 brand new harnesses from British Wiring. Its going well, and everything works properly. I've got a working electrical system with gauges, lights, (and motor that now runs.) The directional indicators are the last piece of the electrical puzzle.

I've been immersed in the DB10 wiring, and have just ordered a Lucas solid state version from British Northwest to freshen up the DB10 box, and take it out of the equation. I have also ordered the indicator flasher for good measure. I have the drawings and OEM manuals and making slow progress. However, the print, aftermarket wiring, and existing hardware all have to mesh correctly. I guess what I was looking for was actual hardware troubleshooting recommendations (check these pins on the DB 10, etc. ) as the DB10 and hazard circuit is definitely where the problem lies. The old harness used a 3 pole hazard switch and has been replaced with a two pole from R. Dent. This changeover, and the assoicated wiring is contributing to the problem. Basically what part of the circuit discontinues the parking lights when they are positioned ON, once the hazard is actuated? I am looking for the logic flow and associated hardware to go after and check..I appreciate the insight.

Thanks guys for your help.

[Craven]

This will keep you occupied for a while, you will be the forum guru on the DB 10 when get your head around this fortunately us with UK cars have no need.
https://www.gglotus.org/ggtech/relaybox/body-relay.htm

[mjbeanie]

Thank you Craven,
I have been studying that and may try the diode that is recommended. Yes you guys in the UK dodged a bullet with the aforementioned, "mystery box". I have two circuits that are work properly, they just overlap one another-when both are switched on.

If I get frustrated, I may just stick my arm out to signal for a left turn.

Thanks!

[HCA]

This will keep you occupied for a while, you will be the forum guru on the DB 10 when get your head around this fortunately us with UK cars have no need.
https://www.gglotus.org/ggtech/relaybox/body-relay.htm

This too I shall file under - 'crap dreamt up by designers'! Thanks for this Craven!

mjbeanie - far from me to tell you what is right or wrong, must you pursue the crazy US light system? You have an English car, using English electrical components, with all the wires extended to the four corners - why not just connect them up as designed?

OK, the original design did not allow for integration of the sidelights into the hazard function, but so what, just physically turn them off if you want to use the hazard function alone...

I might be a bit biased - borne from living in the Ramstein area for a while where 40% of cars were US imports. I see that even now, GM are making cars for the US market that have the amber indicator lens used in the EU version of the car removed with the red light doing all the work. Ridiculous! Where is Ralph Nader when you need him

[mjbeanie]

Thank you for the responses. I will continue troubleshooting. The DB10 adds another layer of complexity but it will get sorted.

[mbell]

I doubt lotus would redesign the wiring and implement it in just US cars for the fun of it. As UK and rest of world cars weren't weird like this.

So I suspect it was done to be compliant with US regulations at the time.

[HCA]

Sorry mjbeanie, Lotus had many faults but lighting not one of them. It followed the then standard in Europe - red to show beware, amber to show an intention and white to illuminate direction.
All very logical and easy and works to this day!
No, it was some not very intelligent person on your side who put you into your predicament

[mjbeanie]

Thanks I will get this sorted. I am getting closer. The indicator system works well. Need to sort the indicator circuit interruption with the Hazard switch on, to activate all corners of the car. The aftermarket harness does not track with the OEM drawing, and the hardware doesn't mesh well at all times with the harness. So it is a bit of a battle.

There are many good bits of information out there, (especially the description and operation that Craven provided) that add some useful clues, however Autosparks harness #1868, is out of specification for a Plus 2S "Federal" model, which is not helping much. (I proved this to Autosparks, and they kindly sent a refund.)

When I have this all done, I will add in final details for those folks that specifically have a Plus 2S 130 with 3 fuse boxes, Federal spec, with the Lucas DB10 Relay Box, Alternator, Aftermarket Harness (from Autosparks), and a DPDT Hazard Switch. Whew..!

As an aside, can someone with a FEDERAL SPEC, 1971 or so, Plus 2S 130 please run a quick test for me. Activate the parking lights to ON, and then then flip ON the hazard circuit. Does it alternate between low brightness and higher brightness? Thank you for the feedback!

I ran across another 72 Plus 2S 130 and this is what both his car, and my car both show, when the parking lights and hazard are both powered ON. All four corners of the car oscillate between low and high brightness. (Of course with the parking lights OFF, all lights will oscillate between Bright and OFF.) Thank you Lotus community for the response!