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Discussion Starter #1
Having experienced several issues with the left side gauge cluster, it was taken apart for trouble shooting. Fortunately all of the wires that plug into the back of the gauge cluster appear to be in the correct location (according to the wiring diagram and the tiny notches on the connector) and “working properly” however there must be an issue between the connector and the actual gauge cluster. The wiring diagram shows ‘wires’ going to each gauge and the gauge lights, when in reality the wire connector plugs into a printed circuit board.

Left Instrument Pod.jpg

At least the speedometer and the ammeter work but the cluster back lights don’t work even though there are 12 volts on the white/black wire (#2) in the connector and other lights like the ‘Fari’ lights are confused and ‘Luci’ not working. Any time the lights are on, the ‘Fari’ blue light is on (indicating high beams) yet there is only 12 volts on the green/black wire (#1) in the connector when the high beams are on. The Luci indicator does not light up yet there are 12 volts on the yellow wire (#5) in the connector anytime the lights are on.

I am pretty sure that the fuel gauge needs to be replaced or rebuilt. Would anyone know where I could get a new Montréal fuel gauge? The sending unit is new and seems to be working. I am pretty sure that I have checked each bulb 2 or 3 times but perhaps they need to be replaced.

Has anyone else experienced similar issues with their gauge clusters? The right side cluster with the tach seems to work fine. I am open to suggestions...somehow misplaced my volt meter.
Mark
 

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Does the clock run? If so, the only explanation I can think of with those particular symptoms is that the left cluster 6-pin connector is rotated 180 degrees in its socket (4). Is that even physically possible? I never had the instrument cluster apart, so I don't know.

The Fari and Luci lights will swap functions is the socket has rotated and the rest will behave very odd or appear to be dead. The ammeter and clock will not be affected since their connections aren't through the socket.

Just for posterity: the wires should have the same colours on either side of the socket when the connector is plugged in.
 

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Discussion Starter #3
Thanks for your reply TorW,
No the clock does not run, I'd be surprised if many (any?) still work after 40 years. I considered buying the one that was on eBay but decided it was probably not worth the trouble since the battery is disconnected after every trip and the construction quality of the clock does not appear to be the best.

I don't know if the connector can be plugged in 180 degrees out. The corners on one side are 'angle cut' to fit the female connector but it is worth looking into. It is difficult to see how the two pieces fit together and I know that I relied on the 'set' of the wires, which could be wrong.

The Fari and Luci lights will swap functions is the socket has rotated and the rest will behave very odd or appear to be dead. Worth looking into!

Just for posterity: the wires should have the same colours on either side of the socket when the connector is plugged in.
Well there are no wires on the gauge side of the connector; you can see the antique printed circuit board in the above picture. Hopefully the connector is 180 degrees out and that would be an easy (embarrassing) fix.
Mark
 

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Hi Mark,
The clock is an electrical-mechanical type. Try pushing the adjusting rod many times and tapping a few times on the casing! It usually gets it going again.

Steven
 

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Hi Mike, mine is still open and out of the car if you want any help to trace down the problem. We can use skype as well. Your volt meter is working? I had problems in the through hole rivets of the copper strips of the PCB due to different materials in touch with one another generating a kind of corrosion and bad electrical contact, something that was fixed with a solder point in each rivet. Apply acid solder paste before soldering in order to clean up the region.
Rgds
 

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Just a data point... My clock works, but runs fast, just like the speedometer. Where's the master calibrate knob? Must be somewhere....
 

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Concur. Time stands still when enjoying a good Alfa in any case.
 

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Mike, here is the connector pinout. If you feed 12V you can trace down the problem. Don, clock speed adjustment can be made through an internal mechanical lever.
 

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Discussion Starter #10
Hi Guys,
Thanks for all your collective help!
TorW, The plug in connector will only plug in one way; not 180 degrees out (darn it).
SHaszz, no luck with the clock either after much tapping and pushing the reset rod...
Edgar, using your numbers we agree on all except I believe #2 (center pin on upper row) is for the gauge back lights. It can be seen on the printed circuit board above. I have a few meters but have not found my newest one but it will turn up eventually, I hope. I'll check the rivet connections again and make sure there is no galvanic corrosion.
Would anyone know where I could find a new fuel gauge?
Mark
 

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Did you ID good LED bulbs for the gauges? It might be nice to actually see them at night.
 

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Discussion Starter #12
I had problems in the through hole rivets of the copper strips of the PCB due to different materials in touch with one another generating a kind of corrosion and bad electrical contact, something that was fixed with a solder point in each rivet. Apply acid solder paste before soldering in order to clean up the region.
Rgds
The more I think about it the more I believe Edgar has the solution...which means the cluster gets to come back out so I can take the big red gang plug connector off the printed circuit board to clean up the contacts. There is little room for error other than the connector or the actual light sockets themselves.

I have not looked into LED's for the Montreal; I try not to create new problems out of old problems. I have only one LED in my entire house. It is in a reading lamp and to my surprise I really like it! The old light bulbs used to heat up so bad they'd burn my fingers or make me hotter than I already was in the summer and they did not last long. The LED stays cool to the touch and even works with the dimmer.

Mark
 

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Discussion Starter #13
My clock works, but runs fast, just like the speedometer. Where's the master calibrate knob? Must be somewhere....
Don, It has been a while since I removed the clock from the cluster but I seem to remember that there is some sort of speed adjuster on the back of the actual clock. You'd have to remove the clock from the cluster (not a big job) but still have a way to power it up to adjust the speed. Then let it run for a day or so and check and adjust it again until you get it calibrated.

I found the attached AROC article in the 'Alfa Owner' with the red Montreal on the cover (June 2000) by Eric Roe, edited by Bill Gillham:thumbup:.
Alfa gauges.jpg

It really pertains to Giulietta Gauges but some of the information may apply to the Montreal gauges.
Mark
 

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TorW, The plug in connector will only plug in one way; not 180 degrees out (darn it).
Well, it was obvious the moment Edgar posted his closeup of the connector. So much for my armchair efforts.

I too think Edgar is onto something, but since I haven't had the gauges apart myself I should probably just lean back and watch :)
 

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Discussion Starter #15 (Edited)
:thumbup:
Well, it was obvious the moment Edgar posted his closeup of the connector...
TorW, I appreciate your efforts; you have been right more often than not!

As it turns out the red "cover" of the connector can be unscrewed from the printed circuit board and rotated 180 degrees which would allow the female side to be rotated 180 degrees as well but I don't believe that will fix the issues. Also, I noticed in M-tEC and on Edgar's photo that their connector 'cover' is mounted the same direction as mine. Furthermore all of the rivets are in excellent condition with no galvanic or other corrosion.

PCB contacts back.jpg

PCB rivets.jpg

Would it be a good idea to build up a few jumper wires to connect the female end on the connector to the male end of the connector and see what effect different combinations make...?

I did manage to locate the adjustment mechanism for the clock, I believe the small set screw on top needs to be loosened, slightly, which will allow the arm to move, creating more or less tension on the clocks main spring to requlate the speed of the clock.

Montreal clock adjustment.jpg

I drove the Montreal to work today and had to make a run to the USPS and back -the long way:thumbup: I did find out that the nuts connecting the heavy wires to the amp meter were relatively loose; now that they are tight the amp meter is much more accurate! Other gauges were not affected.....:chris:
Mark
 

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What a cluster

Hi Mark, few more pics from myside, before, after. Yes, the clock back adjustment screw is the right one from your pic. For future visitors, the Monti clock is hybrid mechanical electronic. Mechanics are reliable but the small PCB transistor with 3 resistors and the pcb motor seems not to be a reliable system.
 

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Discussion Starter #17 (Edited)
Well I am still perplexed by the left instrument cluster and its unusual behavior. I did make up two jumper wires so I could connect just the specific wires required for the Fari (High Beam) or Luci (lights on) headlight indicators and I installed a new bulb for the Luci indicator. Unfortunately the results were the same as before; with the connector in contact with the other half of the connector. No Luci light ever and the Fari lights up whenever the lights are on with the exception of the high beams (when it should light up!).

Edgar, thanks for posting photographs of your repair. I can see that your PCB had a good deal more corrosion but I can't see where there was corrosion at the rivets. I checked the resistance between the copper printed circuit and the rivets and measured 1.5 to 2 ohms. I don't believe this is a great deal but don't know what is acceptable.

Since you did the solder repair have you tested out the cluster to determine if everything works?

I can only handle so much frustration and may need to pull the steering wheel to fill some cracks around the wheel and reseal it while the cluster sits on the back burner for a while.

Mark
 

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Discussion Starter #18
Yes, the clock back adjustment screw is the right one from your pic. For future visitors, the Monti clock is hybrid mechanical electronic. Mechanics are reliable but the small PCB transistor with 3 resistors and the pcb motor seems not to be a reliable system.
Wednesday night I was working on the car and heard two strange noises. I rarely put the windows up but it is getting colder so both windows were raised. One noise sounded like a relay, clicking. The driver’s window switch was still in the 'up' position, I thought it would be 'self cancelling' like the 164's but no, it was 'waiting' for me to put the switch in the neutral position.

The other noise was a 'ticking' noise, my first thought was that it was going to "blow", run... but then I realized the ticking was coming from, you guessed it, the clock! Yes, it ticks but the hands do not move or change; so Alfa created a time machine or sorts, well a way to make time stand still:thumbup:.
Mark
 

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Mark, yes the cluster is working after the revision. I am not sure if your cluster is still out of the car. If not, disconnect the red female conector, ground wire and 12V clock wire. It would be nice if you can get an external 12 V power supply. Attach the black negative terminal at the center terminal of the fuel meter. Now:

1. Feeding the red +12V at pin #5 you get LUCI

2. Feeding the red +12V at pin #1 you get FARI

3. Feeding the red +12V at pin #2 you get the two speedometer lamps

If your cluster is working fine, your problem is coming from the outside: female connector, cables and or panel switches.
 

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Discussion Starter #20
Hi Edgar, thanks for your suggestions. I finally got ambitious and took another look at the speedometer cluster to see if I could get the fuel gauge and gauge back lights working. With the cluster still in the dash, I disconnected the following: gang plug from the red connector, the clock power lead and ground. Using a set of jumper cables with two leads connected to the car battery and the other ends connected to a set of test leads; I was able to hook the negative ground lead up to the lug at the center of the fuel gauge, while connecting the positive lead to the terminals as you suggested:
1. Feeding the red +12V at pin #5 you get LUCI

2. Feeding the red +12V at pin #1 you get FARI

3. Feeding the red +12V at pin #2 you get the two speedometer lamps

The results with 12 volts applied to each pin above, one at a time; I got nothing. No Luci, no Fari and no speedometer lamps. It appears that there must be bad connections like you experienced between the lugs and the PCB.
Thanks for your suggestions,
Mark
 
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