Making Your Flasher Relay LED Compatible Options

[Spoke]

This thread is meant to help those implementing LED turnsignals on their 914.

Standard flasher relays were designed to flash 2 standard bulbs (21W each) for turnsignals or 4 standard bulbs with 4-ways on.

LED replacements burn between 2W and 5W and electrically may not behave at all like a standard bulb. The LED replacements can cause all kinds of weird things like hyperflash (2x normal flash rate), dash indicators do not work, or the the flasher relay does nothing at all.

The 914 flasher is different for early cars 70-73 than later 74+ mainly because of the tach indicators. Early cars have individual L and R indicators and the 74+ have a single L+R indicator. Both are handled differently by the flasher.

There are LED-compatible flashers generally available at your FLAPS which are plug-in but not totally function compatible with the 914 standard flasher. The functional issue revolves around the 4th terminal which the 914 uses to activate the dash indicators.

The aftermarket flasher relays are EP26 (4 terminal) and EP36 (3 terminal). I've seen these at Pep Boys, Autozone, and Advance Auto to name a few FLAPS, usually for less than $15.

I'll detail the differences between early and late cars, as well as EP26 and EP36 in the next few posts.

[Spoke]

Continuing the discussion of the early 914 ('70-'73) with separate left and right turnsignal indicators in the dash, many owners have noticed that the turnsignal indicators sometimes flash together with the OEM flasher. The simplified diagrams below show what is happening.

The diagrams show the flasher when the right turnsignal is selected and the lights are flashing ON. The K lead relay contact is closed when the high turnsignal current with standard bulbs flow through the main contact.

In the left diagram, the secondary relay contact on the K lead is closed and current flows through the RIGHT turnsignal indicator and through the LEFT turnsignal bulbs. In this case the right indicator bulb is much lower wattage and higher resistance than the exterior high power standard bulbs and thus drops almost all the battery voltage and lights up. The small indicator current does not light up the left side exterior bulbs. I'm not sure why it's connected like this but there it is.

In the right diagram, the secondary relay coil for the K relay has weakened over time and lost its efficiency. Now the K relay may close for the first flash or two then totally gives up and remains open like shown. What happens then is the current flows from the 49a turnsignal pin through both left and right indicators and through the left exterior turnsignal bulbs. Both left and right indicators light at a diminished intensity.

The only solutions to this are replacing the flasher with an OEM or EP26 flasher, or disconnecting the center connection to the K lead and grounding the common connection as detailed above. EP26 needs modified internally to short the K/C2 lead to ground. I do this to EP26 flashers that I sell.