TheSamba.com :: View topic - Flasher Relay instalation (4 pin to 3 pin)

Sun Jul 09, 2017 8:55 am

Hi guys, im trying get my indicators working as when i turn them on nothing happens. (on the dash and lights themselves) I am very new to all the wiring and stuff. However I want to learn. I was told i needed a 3 pin flasher relay but when I wire it up it doesnt seem to do anything.
Again I dont actually know if i wired it up right anyway :?

The old flasher was a 211953215C
The new one just says 12V 21WX2+5W MAz. 47W 041015 (which is gobbiltygook to me) :shock:

Il post pictures of the set up I have and the new flasher relay I got and see if any of you know how to do it.....or if its something completly dfferent.

Thanks

(Its a 1970 beetle by the way)

Sun Jul 09, 2017 10:54 am

That relay may work in your Beetle. Do you know if it is the proper replacement for the '71 Beetle? Where did you buy it and what is the make/model on the box?

Maybe the most important indicator if it will work is what are the terminal numbers on the bottom? The stock VW terminal numbers were:
31 - ground
49 (+) - 12v INPUT
49a - OUTPUT
KBL - 4th prong, ground for a dedicated turn indicator lamp
If your previous flasher relay had 4-prongs you will need to splice in the blue/red KBL wire into the #49a OUTPUT wire.
This 3-prong EP35 flasher relay has the proper terminal #s and is LED compatible (not all flasher relays are):

This turn signal indicator lamp in the speedo is where many "generic" flasher relays will have a problem. The blue/red wire from the center-bottom turn indicator lamp in the speedo is a ground wire for the bulb. The three indicator bulbs at the bottom of the speedo share a common 12v+ source and each of the blue wires running from the holders run to a switched ground which will turn the lamp ON.

The #49a OUTPUT terminal will provide 12v+ to power the corner turn signal lamps. In between pulses of 12v+ the turn indicator lamp in the speedo will ground thru all four corner lamps. In incoming 12v+ from the speedo lamp on the 49a OUTPUT terminal will "confuse" some simple flasher relays.

While you are troubleshooting, remove the turn indicator lamp from the bulb holder. Get the turn signals and E-Flasher lights working as expected and then as the final step, re-install the speedo turn indicator lamp and retest everything. If the turn signals and E-Flasher stop working correctly it is a sure sign you have an incompatible flasher relay.

The other thing your flasher relay indicates is that it is expecting the load of two 12v 21W bulbs and a 5W indicator lamp (12V 21WX2+5W MAz. 47W). For a total load of 47W. Your stock indicator lamp is only 2W and so your load will only be 44W. This shouldn't be much of a problem.
But this indicates to me that this relay will NOT work with LED bulbs which typically have a much lower watt rating (1~2W is typical for LED bulbs). These bulbs will be too small a load to work with this relay. Just something to keep in mind if you every plan to replace your turn signals with LED lamps.

Sun Jul 09, 2017 2:00 pm

The relay I bought is a cylinder one that has X,L,P

I have the KBL wire already wired up with the Terminal 49a ( Black w/Green and white stripe)

I bought the relay at my local motor factors.
I put the Brown earth wire on X and the 49a on L and then 49 on P and nothing has happened. then swapped them over and still doesnt work. Would it be something else or the relay itself?

Thanks for the reply

Sun Jul 09, 2017 2:52 pm

markthecreator wrote: The relay I bought is a cylinder one that has X,L,P

I have the KBL wire already wired up with the Terminal 49a ( Black w/Green and white stripe)

I bought the relay at my local motor factors.
I put the Brown earth wire on X and the 49a on L and then 49 on P and nothing has happened. then swapped them over and still doesnt work. Would it be something else or the relay itself?

Thanks for the reply

What is the brand and part number for the flasher?

A google search shows a few diagrams for flashers with the X L P labeling, the connections appear to be:

X = +12V (might be a "+" symbol instead of an "x")
L = Output to turn signal switch (presumably L for Lights)
P = turn single indicator (P=Pilot light)
No ground connection (some diagrams show case as ground, but unless there is a mounting tab that seems unlikely)

Some flashers show L and P to be connected together internally, so DO NOT connect either of those to ground.

EDIT:
Quote: The new one just says 12V 21WX2+5W MAz. 47W 041015 (which is gobbiltygook to me)
Something else to consider, that flasher is rated for two 21 watt bulbs, plus a 5 watt indicator light, with a total maximum load of 47 watts. The same flasher is used for the emergency flashers, so that will not be sufficient for flashing all four lights at once.

Sun Jul 09, 2017 3:25 pm

What is the brand and part number for the flasher?

A google search shows a few diagrams for flashers with the X L P labeling, the connections appear to be:

X = +12V (might be a "+" symbol instead of an "x")
L = Output to turn signal switch (presumably L for Lights)
P = turn single indicator (P=Pilot light)
No ground connection (some diagrams show case as ground, but unless there is a mounting tab that seems unlikely)

Some flashers show L and P to be connected together internally, so DO NOT connect either of those to ground.

EDIT:
Quote: The new one just says 12V 21WX2+5W MAz. 47W 041015 (which is gobbiltygook to me)
Something else to consider, that flasher is rated for two 21 watt bulbs, plus a 5 watt indicator light, with a total maximum load of 47 watts. The same flasher is used for the emergency flashers, so that will not be sufficient for flashing all four lights at once.[/quote]

The brand on the new flasher relay? It is SKYPARTS part no. 1412257
just picked it up at the local motor factors. So even if it did work your saying that it wont have the power to flash all four lights :oops:

Sun Jul 09, 2017 11:34 pm

I'm less than confident that flasher relay will work. It is a generic type and doesn't sound like it was designed for your VW.

First, remove the turn indicator lamp from its bulb holder in the speedo while you initially hook things up. When it is all working, you can put it back and check that it still works.

Connect the white wire from the E-flasher switch to the "X" terminal. X is the 12v INPUT for the flasher relay.
"L" represents LOAD and is the flashing OUTPUT of the relay. This is where the black/green/white wire and the blue/red wire connect.
"P" is PILOT and IS NOT USED in this install. It is meant to provide switched 12v+ to a separate bulb that is permanently grounded. This is the 5W load described in the description of the relay markings. Unfortunately, the turn indicator lamp in the VW speedo uses a shared 12v+ instead of a common ground so it makes no sense for it to have a second 12v+ running to it. The VWindicator lamp works off a switched ground. This is why you have it disconnected for testing and why the "P" terminal is not used. Many generic relays will NOT work with the switched ground VW indicator lamp.

The brown ground wire is NOT USED in this case. Your non-original flasher relay doesn't use a ground connection.

With your wires connected as above (just X and L), test your turn signals and E-Flashers. If the load of the four 21W bulbs is too much for the relay it may start flashing very quickly. This means the flash rate between turns and 4-way may be different.

If it all works (it should because without the turn indicator lamp hooked up the circuit is a common flasher + turn signal circuit) you can reinstall the turn indicator bulb into the speedo. This bulb should be connected to the "L" terminal. If the flasher is compatible it will need to operate with 12v+ coming into the "L" OUTPUT terminal while it is OFF. This is where most generic relays have a problem. If the relay stops working once the speedo indicator is reinstalled it is NOT compatible. See if you can exchange it for a correct replacement.
The correct flasher relay will normally have the terminals numbered the same as stock: 31, 49, 49a.