Turn Signal Problems--Yamaha 1999 Zuma Scooter

Question

My turn signals don't work. Fuses are fine, bulbs are fine, flasher relay is making a buzzing noise when turn signals are engaged. I replaced the flasher relay, but to no avail. Same buzzing noise. When I opened up the old flasher relay, I see that the contact plate that completes the circuit is vibrating rapidly when power is applied, but fails to make good contact. I believe the flasher relay is not getting the proper voltage, but I need help--I don't know what to do. (When I increase throttle, the lights began to illuminate dimly, but don't flash. If I use a small piece of plastic to force the contact plate down, the lights illuminate properly, except they don't flash--just hold steady.) The battery is new, by the way. Thanks in advance!

Answer 1

It sounds like the problem is with the charging system.  The vibrating of the relay means there is not enough current to engage it fully.

To confirm that the problem is with the charging system, disconnect the turn signal relay from the bike's electrical system and see if it works properly when connected directly to a battery that you know is fully charged.  If this works, the next step is to measure the voltage with the motor off, then compare that to the voltage you get while the motor is running.  With the motor on the voltage should be 1-2V higher; if it's less then the charging system is not working.