Electronic turnsignal relay question

[Jon Weywadt]

I was planning to change over to LED bulbs on my Murena. For that purpose I bought an electronic turnsignal relay so I would not have to use cheat resistors. However it won't work, neither with LED bulbs or normal bulbs.

I am wondering if the wiring or polarity for the standard Murena relay differs from others. It is a 3 prong relay. The red wire (nr 3 on the Murena diagram) goes to "+" on the relay, one white wire go to "C" That is "70" on the diagram, and one white wire goes to "70B".

Holding the two relays in the same position The original is labeled C R + and the electronic one, B L E .

Is there anyone who can tell me how the B L E is supposed to connect? Perhaps it is a simple matter of swapping some wires around, but which?

[Anders Dinsen]

I think you just have the wrong relay, Jon, it shouldn't be necessary to switch wiring. See for example:

http://www.vehicle-wiring-products.eu/VWP-onlinestore/relays/flashers.php

But even the electronic relays will start flashing fast with LEDs, as they're designed to do so to warn the driver that a bulb is gone.

/Anders

[Jon Weywadt]

I think you just have the wrong relay, Jon, it shouldn't be necessary to switch wiring. See for example:

http://www.vehicle-wiring-products.eu/VWP-onlinestore/relays/flashers.php

But even the electronic relays will start flashing fast with LEDs, as they're designed to do so to warn the driver that a bulb is gone.

/Anders

Hej Anders.

the relay I got corresponds to the RFL3. My picture does not show it, but the numbers are 49, 49a, 31. It is marked specifically for LED and rated at 12V 0,02 - 20Amp
It looks like I should have gotten a RFL9 type, which is numbered 31, 49a, 49. In that case I should be able to swap the two opposing wires in the socket to make it work.

UPDATE!
I just tried swapping the opposing wires in the socket (31 and 49). Before there was no reaction from the relay at all. With the wires swapped it just sounds like a buzzer. I took it apart and looked at the circuit and rethinking the possibilities, the only thing that makes sense is that + should be on pin 31, which it was from the start. Pin 49 should go to the lamps and 49a to the dash turn signal indicator.

I was expecting the relay to operate wether I had regular bulbs or LED. Perhaps they all need to be LED for this relay to work.

[Oetker]

I also tried to use a led relay, but they are not designed for the electrics the Murena has.
I abandoned the led project for this, because the only solution I found was using cheat resistors with the standard thermal relay.
There is no straight + that is switched by the steering switch to let the electronics do the job.
The goal was to bring current down, and with that kind of resistors it want.
It is only possible to let it work if you change the complete wiring.
I didn't want to do that.
Give the led relays a straight + and -, and you will hear it clicking at a normal speed, but there is no way to switch it of without excessive  modification in the wiring.

The relay I tried.

[Jon Weywadt]

I also tried to use a led relay, but they are not designed for the electrics the Murena has.
I abandoned the led project for this, because the only solution I found was using cheat resistors with the standard thermal relay.
There is no straight + that is switched by the steering switch to let the electronics do the job.
The goal was to bring current down, and with that kind of resistors it want.
It is only possible to let it work if you change the complete wiring.
I didn't want to do that.
Give the led relays a straight + and -, and you will hear it clicking at a normal speed, but there is no way to switch it of without excessive  modification in the wiring.

The relay I tried.

That is tha same relay I tried.  I wish I had known about your attempt.

[Bart_Maztra]

What's wrong with old fashion light bulbs?
 

Most of the led replacement bulbs are cheap chinese shit, and produce less light than normal light bulbs.

[Oetker]

Sorry for not posting all the things I try out.
It was one of my first jobs I did on the Murena.
The lights in this car are glowing nails, and I tried out several led solutions for that.
All my led bulbs are out now except the reverse lights.
The combined led lights with normal and brake light are not good enough in my opinion.
The turn signal lights had the above problem.
I am back to normal bulbs, but placed Philips vision plus in the front and the back that give just a bit more light.

[roy4matra]

I was planning to change over to LED bulbs on my Murena. For that purpose I bought an electronic turnsignal relay so I would not have to use cheat resistors. However it won't work, neither with LED bulbs or normal bulbs.

I am wondering if the wiring or polarity for the standard Murena relay differs from others...

Yes, the terminals are not standard and in different positions to normal Jon.

If you have a totally standard Murena and indicator system, and your flasher unit failed, you could not simply plug in a standard new one meant for a normal car!  I don't know why they did it, but that's French electrics for you.

The electronic flasher you have is correct and to the normal standard.  It is the Murena you need to alter slightly.

It is a 3 prong relay. The red wire (nr 3 on the Murena diagram) goes to "+" on the relay, one white wire go to "C" That is "70" on the diagram, and one white wire goes to "70B".

The red wire is the power, live; the white with red marker (70) goes to the switch; and the white with white marker (70B) goes to the warning light.  Since the electronic flasher unit has a positive and negative, you can see that it will not work in that socket as wired.  But correctly wired up it will work.

Holding the two relays in the same position The original is labeled C R + and the electronic one, B L E .

Is there anyone who can tell me how the B L E is supposed to connect? Perhaps it is a simple matter of swapping some wires around, but which?

The electronic flasher needs a power feed to B which you have (red wire) and an earth to E which you don't have; and the third connection L goes to the switch (70) which you have.  So you need to connect an earth instead of the warning light wire (70B).  However, you then have the problem of the warning light.  Most cars now have one for each side, but the Murena only has one for both.  So this will need to be changed.

The original flasher unit gave a flashing signal to the warning light directly from the unit, but with no cross link.  If you try to use the left or right feeds to the same warning light you could get a cross feed to the other side, so you will need to be aware of this and allow for it.  One way is to have two diodes and stop the back feed that way.  Another is to wire both sides of the warning light one to left and one to right.  Then whichever side is flashing it will use the other side to earth and it will work except when the Hazard Warning Lights are on.  Since you have a separate Hazard warning that is fine.  However, the flasher warning light in the dash uses only one connection and a common earth, so unless you rewired the dash the latter is not easy to. do.  Better to have a feed from both sides to that one connection but through a diode to stop a cross feed.

Roy

[Jon Weywadt]

Yes, the terminals are not standard and in different positions to normal Jon.

My friend Jan and I checked this online and also found that.

The electronic flasher you have is correct and to the normal standard.  It is the Murena you need to alter slightly.

We also tested the relay from an bench powersupply and using an ordinary light bulb found that the relay was OK as long as it was hooked up just like you say.

Most cars now have one for each side, but the Murena only has one for both.  So this will need to be changed.

The original flasher unit gave a flashing signal to the warning light directly from the unit, but with no cross link.  If you try to use the left or right feeds to the same warning light you could get a cross feed to the other side, so you will need to be aware of this and allow for it.  One way is to have two diodes and stop the back feed that way.  Another is to wire both sides of the warning light one to left and one to right. 

I did not think about the cross connection through the warning bulb in the dash. I think I will rewire it so each side from the switch feeds this through a diode, as you suggest.

Then whichever side is flashing it will use the other side to earth and it will work except when the Hazard Warning Lights are on.  Since you have a separate Hazard warning that is fine.  However, the flasher warning light in the dash uses only one connection and a common earth, so unless you rewired the dash the latter is not easy to. do.  Better to have a feed from both sides to that one connection but through a diode to stop a cross feed.

Roy

I am not sure I understand what you say about the hazzard warning light. I thought that the hazzard switch simply used the same flasher relay and just shorted both sides together. Are you saying there is a seperate hazzard flasher relay?

[roy4matra]

Then whichever side is flashing it will use the other side to earth and it will work except when the Hazard Warning Lights are on.  Since you have a separate Hazard warning that is fine.  However, the flasher warning light in the dash uses only one connection and a common earth, so unless you rewired the dash the latter is not easy to. do.  Better to have a feed from both sides to that one connection but through a diode to stop a cross feed.

Roy

I am not sure I understand what you say about the hazzard warning light. I thought that the hazzard switch simply used the same flasher relay and just shorted both sides together. Are you saying there is a seperate hazzard flasher relay?

Start from the beginning Jon.  If you wire the indicator warning light so that you have a wire from the left and right to each side of the bulb, it will flash correctly, since when the left side are flashing it will get a flash feed from the left and earth through the right side bulbs.  Also it will flash for the right hand side, earthing through the left side bulbs this time.  However, with this set up, it will do nothing when the hazard warning lights are on since it will get a feed from both sides, and there will be no earth.  Since, by law you must have a hazard warning light, you would still be legal since there is a separate hazard warning light in the Murena.

If you feed the original wire to the indicator warning light, from both the left and right (via diodes to stop any cross feed) the indicator warning light will still flash when the hazard warning lights are on, since you will get the feeds one side of the bulb, and the bulb will earth as normal through the common dash earth.  So in this case you will have both indicator AND hazard warning light bulbs flashing.

Some cars used a separate flasher unit for the hazard warning lights but the Murena is not one of them.  In fact it is a 'cheap' system, since the flasher unit is permanently live which means you can leave the indicators flashing even when the ignition is off!  Normally the correct way to do this is the relay for hazards should be live and the relay for indicators should be fed via the ignition...

Roy

[suffolkpete]

Slightly off topic, but I needed a new flasher relay for my Murena recently.  Predictably there was no listing for the Murena, so I settled for one for a Rancho, reasoning that most Matra parts came from the same parts bin.  I found that it had four terminals instead of three, the fourth one being an earth.  It was easy to add an earth though as there was a vacant position on the socket in the correct place and the other three connections were the same as the original relay.