Dash turn signals Options

[Cal]

Question.....when I turn on the turn signals in either direction both indicators on the dash board light up at the same time. Any idea what the problem might be?

[toolguy]

You're probably going to find this hard top believe, but check the wattage of the bulbs in all four corners. .
I had this happen when I installed all new bulbs. . After a couple of hours of checking grounds, connectors and circuits, I traced it down to not using the correct wattage bulbs. . Once I put in the old original bulbs the dash indicators worked correctly again.
I never figured out the 'why' of it and chalked it up to the old military electronic explanation that always applies. . "PFM". . Pure F-ing Magic. .

[Spoke]

You're probably going to find this hard top believe, but check the wattage of the bulbs in all four corners. .
I had this happen when I installed all new bulbs. . After a couple of hours of checking grounds, connectors and circuits, I traced it down to not using the correct wattage bulbs. . Once I put in the old original bulbs the dash indicators worked correctly again.
I never figured out the 'why' of it and chalked it up to the old military electronic explanation that always applies. . "PFM". . Pure F-ing Magic. .

I can take a bit of the PFM out of it for you. See the diagram below with the flasher in the top right corner. Notice the 2nd small coil.

When heavy exterior bulb currents flow when the flasher is flashing, the secondary coil connects the "K" lead to 12V. The K lead is connected to a common wire between the dash indicators.

When the heavy exterior bulb current flows, the K lead connects to 12V, thus one of the dash indicators has 12V across it and lights while the other indicator has 0V across it and is off.

2 scenarios cause both to light:
1) Exterior bulb current is not enough to close the secondary relay; both indicators flash at 1/2 voltage.

2) The secondary coil loses its efficiency over time and heavy exterior bulb current doesn't close the secondary relay.

My flasher suffered from the 2) issue. On the first flash, only the correct indicator lit, then on subsequent flashes, both indicators lit. I solved this by removing the common wire between the indicators from the K lead and attached the common wire to tach ground.

This is a common fix. If you do this fix, you'll find the opposite indicator lights. (RT indicator lights with LT side and visa versa). Swapping the bulbs and bulb holders LT to RT will solve the opposite indicator issue.

[76-914]

You're probably going to find this hard top believe, but check the wattage of the bulbs in all four corners. .
I had this happen when I installed all new bulbs. . After a couple of hours of checking grounds, connectors and circuits, I traced it down to not using the correct wattage bulbs. . Once I put in the old original bulbs the dash indicators worked correctly again.
I never figured out the 'why' of it and chalked it up to the old military electronic explanation that always applies. . "PFM". . Pure F-ing Magic. .

I can take a bit of the PFM out of it for you. See the diagram below with the flasher in the top right corner. Notice the 2nd small coil.

When heavy exterior bulb currents flow when the flasher is flashing, the secondary coil connects the "K" lead to 12V. The K lead is connected to a common wire between the dash indicators.

When the heavy exterior bulb current flows, the K lead connects to 12V, thus one of the dash indicators has 12V across it and lights while the other indicator has 0V across it and is off.

2 scenarios cause both to light:
1) Exterior bulb current is not enough to close the secondary relay; both indicators flash at 1/2 voltage.

2) The secondary coil loses its efficiency over time and heavy exterior bulb current doesn't close the secondary relay.

My flasher suffered from the 2) issue. On the first flash, only the correct indicator lit, then on subsequent flashes, both indicators lit. I solved this by removing the common wire between the indicators from the K lead and attached the common wire to tach ground.

This is a common fix. If you do this fix, you'll find the opposite indicator lights. (RT indicator lights with LT side and visa versa). Swapping the bulbs and bulb holders LT to RT will solve the opposite indicator issue.

Jerry, I hate to ask but one of Murphy's lesser known laws is; "If you make something 100% absolutely clear, you will confuse someone". And I am that someone. So I ask; you pull the BL/BK wire from the indicator lamps between the 2 indicator lamps and attach those to the ground lead on the tach? And why that ground and not any ground? That or circle the spot on your diagram. Sorry for the ignorance. (IMG:style_emoticons/default/beerchug.gif) Kent BTW, love my front turn signals now that everyone can see my turn signals. Also, they are a great "Daytime Collision Avoidance" accessory.