[keith_d]

The person who designed the indicator circuit decided to be clever, by making the relay flash faster if one of the bulbs has gone. So when the power consumption drops the indicator goes faster.

LED indicators consume almost no power, so the indicator relay thinks the bulb has gone and starts flashing like fury. Connect a resistor across the LED to waste some power and the indicator thinks you've got a working bulb and flashes normal rate.

Hope this helps,

Keith.