The Stovebolt Site Forums The Shop Area The Electrical Bay Blinker signal switch problem 1952 Chevy Truck

Experiencing problems with my 7 wire, 3 prong flasher, TB 16-12 blinker assembly made in 1964. Blinker/flasher assembly works fine with headlights and parking lights turned on at highway speeds. Problem arises when I roll to a stoplight to turn right or left, the blinker blinks slow and will just sometimes stop blinking all together. Today I discovered If I turn off the headlights and parking lamps my blinker works just fine when stopped. Seems like there is not enough power at idle run my headlights and blinker compared highway speeds. Thanks Hugh.

Are you on the brakes when you're slowing down? Maybe there's an excess load (high resistance short) in either of the rear turn/stop light circuits that pulls the voltage down too far with the brake lights operating along with the turn signals.

Or it's possible that your generator is not working correctly and your battery is on the way out.

You need to get out your multimeter and monitor your battery voltage at various conditions.

Thanks, will take a look at those voltage readings. I have a question, I have been looking at 7 wire blinker assemblies online trying to compair wire colors, they appear to be the same colors regardless of manufacture?

I don't know if the wire colors are standardized between manufacturers.
I bought a switch assembly from Jim Carter - No name on the box indicating manufacturer (8-wire according to the diagram) with the following wire colors.
Left Front - Yellow
Right Front - Green
Left Rear - Orange
Right Rear - Brown
Stop Light switch feed - Red
Flasher feed - Black
Ground - White (this might be #8 if other units are grounded thru the switch mount.)
Switch blinker indicator feed from flasher - Blue (or maybe this is #8 that might not be on all units.)

Looking on the web at various diagrams, they're NOT the same.

I appreciate the wire diagram color chart. Thinking about replacing that 7 wire signal blinker switch with a 4 wire switch. Am I creating any problems by doing this? Red and black wires go into the 3 prong flasher with the black out to power, leaving me with green and yellow wires to hook up. Guessing those two wires are for the right and left turn signals and 4 way flashers when activated. Thanks Hugh.

Changing to a 4 wire blinker switch will require that you have separate bulb filaments for turn signals and brake lights on the rear. I have no idea if the colors for a 4 wire switch would match a 7 wire switch, but the two output wires on a 4-wire switch would activate the left and right signal lights. The other two wires would be input from power and flasher.
Here's a wiring diagram for a 4-wire turn signal switch.

DO NOT change to a 4 wire, you will be causing more problems as Kevin says. The cause of your problem needs to be determined, not guessed at or start replacing the whole thing. It already works. Several possible reasons for your issuue that take a troubleshooting procedure.
Some thoughts are.
1. Low/failing battery. What is voltage of battery at rest, motor off?
2. Generator/voltage regulator. What is output of generator at idle and high idle?
3. Loose/corroded ground somewhere. Clean all battery cables, posts and any ground straps connections you find.
4. Bulb failing. Look for dim or jittery bulbs.....or dead bulb.
5. The switch. Any work done lately on any electrical whatsoever?
6. Try to simulate the problem at home so you can walk arounnd truck and inspect each bulb's function at various motor speeds and light loads. Don't dwell on wire colors at this time.
7. Report your observations and if you have done the above tasks/tests. You will need a multimeter and nice to have an "ice pick" style tester.