Turn signal problem

I'm having trouble with the turn signals on my 77 KZ1000. I am using aftermarket signals and an electronic flasher. The turn signals work great with the motor off. If the motor is running, the signals either won't flash, or flash very fast. The hazards work fine with the motor off or on. Any ideas????

Thanks

There are really only two things that change when running (as opposed to battery only).

1) The system voltage rises from 12.6V to 14V.

2) There could be some AC noise and ripple on the system voltage, depending on where you look.

It sounds like the flasher unit is freaking out from one of those two things. The flasher I designed uses a 555 timer (I thought most did), so the flash rate should not really increase much going from 12V to 14V.

It really sounds like something is wrong with the flasher.

bountyhunter wrote:

The flasher I designed uses a 555 timer (I thought most did)

The one I took apart uses a U643B or U643B3.
datasheet

Post edited by: loudhvx, at: 2008/03/06 14:04

loudhvx wrote:

bountyhunter wrote:

The flasher I designed uses a 555 timer (I thought most did)

The one I took apart uses a U643B or U643B3.
datasheet <br><br>Post edited by: loudhvx, at: 2008/03/06 14:04

Interesting product, looks like they are integrating everything into one chip. Silicon sure is getting cheap these days.

Yeah. I have the actual schematic for the Wagner 7060 electronic flasher using that chip. The flasher still uses a relay, I assume to handle much higher loads (as it's called a "heavy duty" flasher).

I have it here on my flasher/integrator page:
www.geocities.com/loudgpz/GPZturnSigInteg.html

Some observations:

Lamp outage is indicated by frequency doubling during
hazard warning as well as direction mode.

You say the frequency goes faster when running? Sounds like this may be kicking in.

The external resistor shunt shown as R3 must be selected to match the external load to make the thing "detect" properly. If you went from standard bulbs to LED bulbs and the value of R3 didn't change, it is going to see the lower current as a bulb failure anf fast flash.

Pin 7, Lamp outage detection
The lamp current is monitored via an external shunt
resistor R3 and an internal comparator K1 with its
reference voltage of typ. 81 mV (VS = 12 V). The outage
of one lamp out of two lamps is detected according to the
following calculation:
Nominal current of 1 lamp: 21 W / (VS = 12 V):
Ilamp = 1.75 A
Nominal current of 2 lamps: 2 x 21 W / (VS = 12 V):
Ilamp = 3.5 A.
The detection threshold is recommended to be set in the
middle of the current range: Ioutage 2.7 A
Thus the shunt resistor is calculated as:
R3 = VT (K1) / Ioutage
R3 = 81 mV/2.7 A = 30 m.
Comparator K1‘s reference voltage is matched to the
characteristics of filament lamps (see “control signal
threshold” in the data part).

I suppose it's possible that at 12V they draw a little more current than 14V, so that satisfies the flasher and it flashes OK?

Do you know how much current your turn signals are drawing in operation?

Post edited by: bountyhunter, at: 2008/03/06 14:27

fordtruck wrote:

I'm having trouble with the turn signals on my 77 KZ1000. I am using aftermarket signals and an electronic flasher. The turn signals work great with the motor off. If the motor is running, the signals either won't flash, or flash very fast. The hazards work fine with the motor off or on. Any ideas????

Thanks

If it's one of the see-through heavy duty flashers, I had the same problem. With vibration, some of the solder connections inside the case crack. I was able to cut it open and re-solder it... not pretty, but worked.

If this is a new flasher then this is probably not the problem.

Also, are you sure you're wired into a constant 12v source. There are wires on the bike which will have 12v constant when the bike is not running, but will be swtiched on/off when the bike is running.

Post edited by: loudhvx, at: 2008/03/06 14:30

loudhvx wrote:

fordtruck wrote:

I'm having trouble with the turn signals on my 77 KZ1000. I am using aftermarket signals and an electronic flasher. The turn signals work great with the motor off. If the motor is running, the signals either won't flash, or flash very fast. The hazards work fine with the motor off or on. Any ideas????

Thanks

If it's one of the see-through heavy duty flashers, I had the same problem. With vibration, some of the solder connections inside the case crack. I was able to cut it open and re-solder it... not pretty, but worked.

If this is a new flasher then this is probably not the problem.

Also, are you sure you're wired into a constant 12v source. There are wires on the bike which will have 12v constant when the bike is not running, but will be swtiched on/off when the bike is running.<br><br>Post edited by: loudhvx, at: 2008/03/06 14:30

It is a see thru flasher. It was on the bike when I bought it. I took off LED signals and put on standard bulb signals. It's possible that I damaged the flasher when I installed the new signals. I wired the new signals backward which caused a short to ground. I have a new flasher that I'm going to try this weekend.