Hi SCB,
Yesterday I finally got round to changing the indicator LED's in the rear.
I used the Twenty20 ones for the front and they work fine without any Hyperflshing whatsoever, but they don't do the WY16W equivalent for the rear at the moment so I bought the rather expensive "Cree Bulbs" from LedPerf.com which claim 100% guaranteed against hyper flashing and Cambus errors.
Guess what? as soon as I fitted the "Cree bulbs" to my MG ZS EV I got Hyperflashing! so had to refit the incandescent bulbs back in.
I must admit the Red Stop/Tail and Tail LED bulbs in the rear make the car look great, much better than the "washed out red" look of the incandescent bulbs, but for me I have given up on the indicators unless anyone else had had success changing these without creating hyperflashing.
One solution would be to change the flasher relay for an electronic type, not on option on this type of vehicle as the flashing evidently (I have found out) is controlled by the cars management computer, so no flasher relay installed at all.
I don't want to go down the route of installing resistors, as for heat dissipation, you have to drill and screw the body of the resistors to the bodywork of the car - not an option on a new car.
But at least the front LED's look good and more distinguishable over the previous bulbs.
Andy (Blackpool)