The Lotus Grand Tourers

Has anyone tried converting their indicators to LEDs?

I just ordered a pair of bulbs (only trying the rears for now) and a flasher relay from Better Car Lighting. The bulbs are good, appreciably brighter. However, when I try to swap in the relay they supplied, it blew the fuse. Same outcome either for indicators or hazard lights (I didn't repeat too often, to avoid running out of spare fuses!). Put the old relay back in and it works fine (with old bulbs or LED, albeit flashing too fast with the LED bulbs), so it's definitely the supplied relay that's the problem.

According to Gil at Better Car Lighting, some cars use a Bosch relay where one of the pins goes to earth, which is different to the relay used on other cars. If that is the issue, he has a different relay that will work with that system.

Has anyone been down this road already and know the answer? If not, I'll start digging in to wiring diagrams and try and work it out...

These are pics from the website, what turned up doesn't look identical but it's probably just cosmetic.

The new flasher relay:



And the bulb:

Could it be because you have a mix of conventional bulbs (front) and LED (rear) ?

Andy

AndrewWebber wrote: Mon Apr 24, 2023 12:52 Could it be because you have a mix of conventional bulbs (front) and LED (rear) ?

Andy

The supplied flasher relay is supposed to cope with one, the other, or any mixture, hence the wattage rating that's printed on it.

I've had COB leds fitted in the rear lights of my Excel for several years and can recommend them. They are very bright and durable and plug straight in with no need to change the flasher unit. Last year I bought a pair for the front indicators so I can confirm it's possible to run leds at one end and ordinary bulbs at the other without any problems

https://www.aliexpress.com/item/3242076 ... whnyk5s4LI

KevW wrote: Mon Apr 24, 2023 13:37 I've had these leds fitted in the rear lights of my Excel for several years and can recommend them. They are very bright and durable and plug straight in with no need to change the flasher unit. Last year I bought a pair for the front indicators so I can confirm it's possible to run leds at one end and ordinary bulbs at the other without any problems

https://www.aliexpress.com/item/3242076 ... whnyk5s4LI

Interesting - presumably they must contain a parallel circuit with a resistor that carries a much larger current than the actual LED bulb, so the flasher sees the expected current and continues to work as intended. It misses the benefits of putting a lower load on the car wiring (but that wiring is, of course, well capable of carrying the full load), and the energy saving of the LED (which is miniscule compared to the other energy uses going on). But does seem an easier fit, and is cheaper than the ones I bought! Oh well, I've got mine now so I'll persevere for a bit, but if I can't get it to work I'll try your route!

rbgosling wrote: Mon Apr 24, 2023 10:24
According to Gil at Better Car Lighting, some cars use a Bosch relay where one of the pins goes to earth, which is different to the relay used on other cars. If that is the issue, he has a different relay that will work with that system.

Most cars (as our Lotus) have a flasher with power in (49), power out (49A) and ground (31). This type start with lights on, and switches off when the filament has heated up. There is an alternative type which needs to heat up for the lindicator te be switched on, which only needs two contacts, and could have a third for an indicator light

Looks like your Chinese relay connects the power to earth ie pnk green to black when plugged in.

Have you seen the posts on TLF "sympathy flashing" .
Just something to watch out for - easy fix.
Tony

I retained the small incandescent bulbs in the front wing repeaters on my car so I would imagine they'll cover any need to have a bulb somewhere in the circuit.

I was sent a replacement relay - for reference the correct relay is a CF14. Everything working a treat now!

And I must commend Better Car Lighting for the excellent customer service. Gil responded very quickly to emails with excellent advice, made a real effort to help. Things were sent out promptly, and when I had the wrong relay he sent the replacement, didn't demand the old one back, and no additional charge.

Good to hear you got your leds sorted Richard. The difference between led and standard indicator bulbs on a bright day is really noticable