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.

[Geezer914]

Converted the EP26 flasher. Turn signals work fine. Why does the turn signal indicator flash when the emergency brake is applied? This is on my 75 914.

[rfinegan]

Watching...my 75 is now flashing with the parking brake too, did not have this issue in the past prior to the swap...any ideas?

Converted the EP26 flasher. Turn signals work fine. Why does the turn signal indicator flash when the emergency brake is applied? This is on my 75 914.

[Spoke]

Watching...my 75 is now flashing with the parking brake too, did not have this issue in the past prior to the swap...any ideas?

Converted the EP26 flasher. Turn signals work fine. Why does the turn signal indicator flash when the emergency brake is applied? This is on my 75 914.

The OEM flasher relay in the '74-'76 914s serves a dual purpose:

1) Flash at normal speed for turnsignals with tach indicator flashing
2) Flash at normal speed for e-brake and MC warning switch w/o tach indicator flashing.

The OEM flasher relay does not hyperflash (2x normal rate) if a turnsignal bulb is burned out like 99.99% of vehicles made. To alert the driver that a turnsignal bulb is burned out the flasher does not flash the single L/R tach indicator. Porsche achieved this by adding a 2nd relay and coil to the flasher. If the flash load is 2+ bulbs, the L/R indicator flashes. If the flash load is 1 bulb, the L/R indicator does not flash.

This characteristic allowed Porsche to dual use the flasher relay for the e-brake and MC warning switch on.

Unfortunately when switching to LED turnsignals the OEM flasher relay will never pull in the 2nd relay and the L/R indicator will be inoperative all the time.

In EP26, the K/C2 pin driving the L/R indicator is connected to 49a which is the flasher output. If the turnsignals are on, or the e-brake, or the MC warning light, the L/R indicator will flash.

Since LED turnsignals draw such little current, it is virtually impossible to discern the difference between the LED current and the brake warning light current. About the only way to resolve this is to install a 2nd flasher relay just for the e-brake/MC switch or rewire the e-brake/MC switch lamp to go straight to 12V and just come on full when active.