Topic: 1975 400f rear blinker woes

[watson8r]

Hi All - Last month had me losing a battle against a short somewhere in the wiring harness. With my tail between my legs and multi-meter in hand, I decided to take the plunge and buy a new harness. I saw some questionable sections in my travels and decided to start afresh.

After connecting the new harness I am unable to get my running lights for the rear blinkers or brake light to work. I've checked the harness a few times and run wires separately to test circuits. At the end of the day I could just rewire those lights but I wanted to make sure I wasn't making some bone head mistake here.

Thanks!
T

[MD]

Let me qualify this answer by saying I have a 550 but I believe the 400 is similar.  The fuse box does not have power coming to one side directly from the battery.  There are connectors near the starter solenoid that spread the power.

-MD

[MoMo]

rear blinker running lights? When the brake pedal is depressed or front lever squeezed do you have  power at the green/yellow?

[watson8r]

Checked the fuse connectors and everything was good

Green and yellow wire gets a signal when the brake level or pedal is depressed. Check the filaments on all bulbs and they are still glowing when I attached to a 12v source

[MoMo]

Are there single filament bulbs in the rear t/s? It sounds as though you are saying you have rear running lights on at all times...Larry

[Bodi]

The rear lights are turn signals only, no running lights. Do the signals work?
The tail light is oddly wired but the brake light should always work with key ON. If it's just the tail light not working, you probably need a jumper to replace the (deleted for always-on headlight) headlight on/off switch (unless you actually have one!). This goes on the harness connection ratsnest under the tank, between the black and the brown/black wire (to the TAIL fuse) coming out of the main harness. If you do have a headlight on/off switch, the brown/black wire should have power when key and headlight switches are on.
If the brake light isn't working, check for power at the brake lever switch with key on and that the switch is switching (position is adjustable). If good, look for power on the green/yellow wire under the seat where the stoplight is connected to the harness. Since the tail/stop lamp unit is rubber mounted, the ground connection may be bad?

[watson8r]

Single filament for blinkers and dual filament for brake light. I checked the connections on the harness from the rear up to the headlight enclosure. Good ground connection and no issues with the Orange/Blue leads. The running lights are on in the key 1 position but only the front blinkers.