pereirac wrote:The flasher units are based around an electromechanical thermal switch and if the voltage drops due to too much load the unit is unable to switch. I fixed the problem by fitting an electronic flasher unit instead of the electromechanical unit. It could be a simple earthing issue (do either the left or right indicators flash) or something more. If you have a dynamo rather than an alternator it could be the load?
This is a different aspect of a similar post I made on a recent thread. In both cases, the issue is that there is insufficient amperage flowing through the relay trip circuit to trip it. However, I now realize there are two potential causes and will repeat both here.
1. The one noted above. Amperage is reduced in most cases if the supply voltage falls below what the circuit expects. The related lights still operate under this condition, but are dimmer than normal.
2. Use of modern devices in the switched circuit that draw less current. Replacement of incandescent bulbs with modern LED counterparts will typically result in current draw being reduced to around 15% of the original circuit. While desirable for the health of your Lucas wiring, mods like this aren't necessarily compatible with current-sensing flashers.
On the Europa list a few years back, there was a post from a serious originality freak
who had inserted an electronic replacement in the original relay can and offered pictures and specs.
Do note that not all auto parts store "electronic relays" use a separate timer circuit that is independent of circuit current load. I bought a few when I did my LED switchover that claimed to solve this problem but still used current sensing and therefore would not work with LEDs. My solution was to replace only the rear lamps (the ones I felt were critical for safety) with LEDs. This raised the current draw sufficiently to trip the original relays at a satisfactory interval.