Try the bulb. A failed bulb causes the others in the system to go faster. Is there water inside the lens? That causes corrosion and shorting.
If ok check the earth. Also, MMC use bullet connectors and the ones under the front wing are VERY exposed to road spray and can corrode. I have had similar symptoms to you twice.
Rear indicator poor earth, found by doing a wiggle test of wires under the rear arch where they go through to the lamp. The riveted connection inside the lamp had worked loose.
Front bullet connectors replaced by spades with shrink wrap to seal. Water inside as well, used the “drill a drain hole “ solution!
Last edited by sospan; 06/03/21 10:45 AM.