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Author Topic: Instrument panel, problems and fixes  (Read 13733 times)
Jon Weywadt
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« on: June 28, 2009, 12:14:20 pm »

Yesterday I started by adjusting the frog eye mechanism so it would lock them in the open position if the vacuum is lost. Next I looked for the vacuum leak that had made them shut as soon as the engine was turned off. I found it on the hidden side of the hose on the vacuum chamber. It had a split about 1" long. After I cut the split off I noe have vacuum enough to open and close the lights 2-3 times with after the engine is turned off. All this took about 15 minutes and since I had dedicated the day to my girlfriend, Murena Cheesy I decides to take a look at the instrument panel.

The instrument panels row of indicator lights, to the left of the guages (photo), never lit up on my panel. I had checked the bulbs, which you can reach from the back, and they were all ok. So I disconnected the spedometer cable, freed the odometer reset cable and popped the panel out. There is not much room to disconnect the center connector on the panel, but squeezing it on the right and left side frees it and it can be pulled out.

What I found did not look promising at first. The leads are on a flexible plastic sheet and at the connector and several of the lamps, the copper had seperated from the plastic. (photo)The result is that when you pull a lamp, or the connector, the lead pulls back too and folds up. When you push them back in there is no guarantee that they straighten out again, leaving an open circuit. I fixed that on the connector by first applying contact glue to the plastic and the leads. When it had dried they stuck to the plastic again and made good contact (photo). A couple of the lamps had the problem too and on one of them the leads had broken off. I repaired that by soldering a piece of copper wick onto the remaining lead and cut it to length. (photo)

While I had the panel off I decided to check the volt meter to find out why it didn't seem to work. It works by a thin wire heating a bi-metal arm, that is supposed to transfer the movement to a pin on the instrument needle. I found that it was probably manufactured wrong and since others seem to have problems with it, they probably all are made the same. The problem was, that the angle between the slit in the bimetal arm and the line between the pin and the pivot point on the needle, was nearly 90 degrees. Thus, no matter how hard the bi-metal pushes on the pin, the frictioon prevents it from moving the needle. The solution is to take a pair of needle nose pliers and carefully bend the slit up so it is nearly vertical (photo), then bend the bimetal until the needle again sits at zero. This gives a more open angle that allows the pin to slide in the slit (say that ten times fast Grin) and the instrument now works. Smiley
« Last Edit: June 28, 2009, 05:07:08 pm by Lennart Sorth » Logged

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Jon Weywadt
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« Reply #1 on: June 28, 2009, 12:39:03 pm »

There wasn't space enough for the last picture showing the voltmeter and some of the lamps working.
From left to right they are "lights on", "hazzard flasher on", "High beam on", these three are on.
The remaing are "low fuel", "brake pad warning", "frog eyes open"(I think"), and "charging light".

Should the charging light not come on when you turn on the ignition and extinguish when the engine starts? Mine doesn't. Neither does the frog eye indicator light up. T

here are several modifications made to the wiring on my Murena, so it is hard to tell what should work and what not. For example, I have a push button that pop the lights up and turn on the low beam. If I don't have that pushed, then turning the light switch two clicks and pulling the arm down, pops the lights up and turn on the high beam. If I then push that button, the low beam also come on. I can also turn on the spot lights and now have everything on.  Grin High and low beams on at the same time will probably fry the bulbs in a hurry.  Sad
« Last Edit: June 28, 2009, 05:16:25 pm by Lennart Sorth » Logged

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Oetker
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« Reply #2 on: June 28, 2009, 03:46:40 pm »

This looks a bit different on mine.

After fuellight I have handbrake choke and generator light.
The generator light should come on if contact on.
The wire for this lamp is coming directly from the generator. (connection L)

Also my plexiglass panel was in bad state.
On the wall in the livingroom this is missing now.

I did this with it Angry




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I feel like Jonah, only my fish looks different.
Murena 2.2 Red 1982. Murena 1.6 black on places.
Lennart Sorth
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« Reply #3 on: June 28, 2009, 05:24:29 pm »


The remaing are "low fuel", "brake pad warning", "frog eyes open"(I think"), and "charging light".

first of all, I took the liberty to resize your pictures - which makes them somewhat easier to look at, however I may have messed up the order they were attached in.

Secondly, the symbol you call "frog eyes open" is intended to light up incase of fault in the vacuum system, but I don't think I have seen a car where it was ever fitted/worked.

Charging light should come on when you put on the ignition on - and stay on until the engine produces more electricity than it consumes. Be aware that the bulb itself is part of the circuit - in conjunction with a resistor which should be wired in parallel with the bulb (behind the dashboard).

The volt-meter was not manufactured wrong - it works on most cars, but since the scale is 10-14 V (I think) it means that any poor connection between the battery/fuse-board and dashboard will cause it to read rather low.  A 90 degree offset is not something I have heard of before - maybe a previous owner tried to "fix" the low reading and got it all wrong ?

The green backlight makes me think this is a (modified) Bagheera dashboard - or did the Murena also come with green backlight ?

/Lennart
« Last Edit: June 28, 2009, 05:26:17 pm by Lennart Sorth » Logged

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Murena 1983 1.9i silver // Alfa Romeo Giulietta 2.0d 2012 white // Smart 4two cdi 2010 blue //
suffolkpete
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« Reply #4 on: June 28, 2009, 08:04:34 pm »

The frog-eye light should light when the ignition is on and there is no vacuum.  Looking at the wiring diagram, it appears that there should be a vacuum switch somewhere that applies an earth when there is no vacuum.  I have never seen one though and have no idea what it should look like.  The handbook I have shows the same lamp as a choke warning lamp, so I guess it was changed at some stage later on in production.
As Lennart says, the charging light should come on when you turn the ignition on and go out when the alternator starts to charge.  This lamp is an essential part of the charging circuit as it supplies the initial excitation current to start the charging process and the alternator will not work without it.  The first thing I would do would be to connect a voltmeter across the battery terminal while the engine is running to see if the battery is being charged.  You should see at least 14 volts.  If not, then either there is a break in the lamp circuit or an alternator fault.  Connect  a 12 volt test lamp (a side lamp bulb for example) between the B terminal and the L terminal on the alternator.  If it lights then the alternator is ok.
As you've discovered already, most electrical faults on French cars are due to the connectors.
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Jon Weywadt
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« Reply #5 on: June 28, 2009, 08:31:11 pm »


The remaing are "low fuel", "brake pad warning", "frog eyes open"(I think"), and "charging light".

first of all, I took the liberty to resize your pictures - which makes them somewhat easier to look at, however I may have messed up the order they were attached in.

Secondly, the symbol you call "frog eyes open" is intended to light up incase of fault in the vacuum system, but I don't think I have seen a car where it was ever fitted/worked.

Charging light should come on when you put on the ignition on - and stay on until the engine produces more electricity than it consumes. Be aware that the bulb itself is part of the circuit - in conjunction with a resistor which should be wired in parallel with the bulb (behind the dashboard).

The volt-meter was not manufactured wrong - it works on most cars, but since the scale is 10-14 V (I think) it means that any poor connection between the battery/fuse-board and dashboard will cause it to read rather low.  A 90 degree offset is not something I have heard of before - maybe a previous owner tried to "fix" the low reading and got it all wrong ?

The green backlight makes me think this is a (modified) Bagheera dashboard - or did the Murena also come with green backlight ?

/Lennart

At first I thought that someone had put a green plexiglass instead of the clear one in my instrument panel. But after I took it out I found that it had all the correct maskings on the backside, so it looks like it is original.

I visited Jan today and we talked about the lamps. On his Murena there is a "chokeer" symbol where mine has that "frog eye" symbol. I have not found any vacuum switch anywhere and have not been able to trace the wire. I have had my gear shifter console out and there definitely is no "choker" switch there. Mine is an '82 and Jan's is an '83, so they did make changes. Jan's also has the taillights housing as an integral part of the frame, where mine just sticks through the frame and require covers on the inside (missing on mine Sad )

I saw Jan's charging light work, so I guess I will be trying to find if it is just a bad connection. I did check the bulb and the car starts and charges the battery normally (14,5V across battery when idling)

I think someone probably bent the bi-metal in the volt meter so the angle was wrong. My volt meter now starts with the needle all hte way left and after 10-15 seconds move up to mid way. Before it was stuck left, all the time and when I tried to push the bi-metal to check the movement, it would not budge, because the bi-metal was pushing the pin on the needle exactly towards the axle it pivots around. The vector of the force had no angle to make the pin slide in the slit.  Cool
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suffolkpete
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« Reply #6 on: June 28, 2009, 10:28:16 pm »

Quote
I did check the bulb and the car starts and charges the battery normally (14,5V across battery when idling)
That means you have a good connection to the alternator via the parallel resistor, so the fault must be fairly local to the bulb connections.  I just checked my official 1981 service manual and there is definitely a vacuum warning light and a sender shown.
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Oetker
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« Reply #7 on: June 28, 2009, 10:38:33 pm »

quote
------
That means you have a good connection to the alternator via the parallel resistor.
====================================================

That depends if the original atenator is still there.
Some altenators don't need the +12 on the L or D+ connection after reaching 1500 rpm once.
However my bulb didn't work to.
I ended up puting a new wire from the connector in the engineroom (The one below the electronic ignition.
From the front comes a red/black wire wich needs to go to L+/D+ on the altenator.
Somewhere in the wiring loom in the enginebay it was broken.

The red/black wire comes from the resistor.
« Last Edit: June 28, 2009, 10:43:46 pm by Oetker » Logged

I feel like Jonah, only my fish looks different.
Murena 2.2 Red 1982. Murena 1.6 black on places.
Jon Weywadt
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« Reply #8 on: June 30, 2009, 12:24:41 pm »

quote
------
That means you have a good connection to the alternator via the parallel resistor.
====================================================

That depends if the original atenator is still there.
Some altenators don't need the +12 on the L or D+ connection after reaching 1500 rpm once.
However my bulb didn't work to.
I ended up puting a new wire from the connector in the engineroom (The one below the electronic ignition.
From the front comes a red/black wire wich needs to go to L+/D+ on the altenator.
Somewhere in the wiring loom in the enginebay it was broken.

The red/black wire comes from the resistor.

I don't recall seing such a resistor on my connector. I will check to see if it maybe broke off.
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« Reply #9 on: June 30, 2009, 01:33:45 pm »

If the resistor isn't there and the bulb not working then I suspect the original altenator isnt there because this circuit is needed to give a coil in the altenator 12 Volt.

The resistor is paralel mounted to the charging bulb.
Here a calculation and example of the circuit.

There is a fault in the calculation, but you can replace resistor and bulb with a bulb of 3.5 Watt 12Volt.
Testing the dynamo circuit can be done with a bulb of this specs.
Put it between B+ and  (L or D+)


« Last Edit: June 30, 2009, 01:39:41 pm by Oetker » Logged

I feel like Jonah, only my fish looks different.
Murena 2.2 Red 1982. Murena 1.6 black on places.
Jon Weywadt
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« Reply #10 on: June 30, 2009, 10:46:11 pm »

If the resistor isn't there and the bulb not working then I suspect the original altenator isnt there because this circuit is needed to give a coil in the altenator 12 Volt.
The resistor is paralel mounted to the charging bulb.

Looking at your diagram, one side of the bulb is connected to the battery positive (through the ignition switch) and the other side is connected to the positive output of the alternator. When the engine is off the current runs through the bulb when the ignition switch is turned on and through the alternators stator winding to ground. Once the engine starts the bulb will have the same voltage on both sides and extinguish. So why use a resistor? Is that to provide exitation voltage to the alternator? Do all alternators require this? because I don't seem to have the resistor, or maybe it is located somewhere else on my car.  Huh
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« Reply #11 on: June 30, 2009, 11:03:23 pm »

The resistor comes in when the bulb blows, giving the altenator the needed 12 Volts, so it wil start working.
In modern cars this bulb is around 3 Watt, where in the Murena it is 1.5 Watt.
As you see in the diagram bulb en resistor together give a load of 3.5 Watts.
The original atenator will work if the bulb or the resistor or both are there.
It wil not work if both are not there.
Thats why I think you have a newer type of altenator.
That doesn'need either one to kick in.
Ofcourse it is possible that someone located the load elsewhere.
You have to look near youre altenator, because that would be the place to do it.
« Last Edit: June 30, 2009, 11:16:48 pm by Oetker » Logged

I feel like Jonah, only my fish looks different.
Murena 2.2 Red 1982. Murena 1.6 black on places.
Jon Weywadt
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« Reply #12 on: December 30, 2009, 03:57:11 pm »

The resistor comes in when the bulb blows, giving the altenator the needed 12 Volts, so it wil start working.
In modern cars this bulb is around 3 Watt, where in the Murena it is 1.5 Watt.
As you see in the diagram bulb en resistor together give a load of 3.5 Watts.
The original atenator will work if the bulb or the resistor or both are there.
It wil not work if both are not there.
Thats why I think you have a newer type of altenator.
That doesn'need either one to kick in.
Ofcourse it is possible that someone located the load elsewhere.
You have to look near youre altenator, because that would be the place to do it.

I finally got around to checking the ignition light on the instrument panel. The bulb is OK and the resistor IS there, but hidden. With the panel disconnected, i measure +12V on both sides of the resistor. This indicates that pin "9" is not connected to ground through the alternator stator winding. The alternator is probably a new type that does not require this. The question is, how then to make the ignition light work?

I got into this while I was trying to find out why the starter selenoid suddenly quit engaging. That turned out to be a bad connection on the selenoid, not the start switch as I first thought.
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« Reply #13 on: December 30, 2009, 06:59:24 pm »

The wire from the bulb is red/black, and goes straight from there to the connector in the engine room (near the HT coil).
From there it goes true the wiring loom of the engine bay to L on the alternator in case of Paris Rhone brand.
If it is another brand alternator and you have connection D+ it has to go there.
In my case the wire in the wiring loom was broken somewhere.
I did replace it with a wire straight from the connector to the alternator.
It fixed my problem.
It looks like the same problem in your case.
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I feel like Jonah, only my fish looks different.
Murena 2.2 Red 1982. Murena 1.6 black on places.
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