Instrument cluster wiring issues.

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Instrument cluster wiring issues.

Postby 123-jn » 13 Jan 2018, 20:36

Recently my instrument cluster has been giving a bit of grief. I read an excellent article on the Wiki by Covkid and Ghost and decided to make the circuit shown. I used an old atx plug and socket and lebelled all the leads. I also selected a better resistor value for the blue LED making it Much less bright. (68K). Imagine my surprise when I took my instrument cluster out to find that the later clusters have a different pin ot and a more complex wiring circuit. Sadly my flexi circuit is rather weak and feeble so I did not mess with it too much. I would have liked to spend some time drawing the diagram to go in wiki but as I needed the van I used some thin wire links soldered on to the tracks to repair the High beam, clock and backlights. Drawing the circuit will have to wait.
Here is the pin out for the cluster connector on a 1989 1.9 petorl Komet camper.
1. +ve feed from variable resistor for dimable backlights. grey/blue
2. Highbeam telltale (Fernlight) which means far-light Blue/white
3. Ground (Labelled -ve Alt gen) Brown
4. Linked to 6 (labelled Frei temp) translated to unrestricted temp no lead
5. Clock +ve (labelled UHR) Red
6. Temperature gauge ( Labelled 'Temp') yellow/red
7. Fuel Gauge Purple/Black
8. ALT +ve (labelled +ve Alt gen) Black
9. Labelled KLI (haven't a clue) Green
10. Indicator telltale (labelled Blinkr) Blue/red
11. Ladelcontr (translates to levelcontrol) Blue
12. Oil pressure 1.6bar (buzzer of Doom) yellow
13 Oil pressure 0.5 Bar ( Light) blue/black
14. Diesel glow or Catalyst/Oxy light (inj models) White/red
The circuit contains an extra Diode on the oil pressure circuits and a capacitor on the instrument backlight circuit. I replaced my resistor for the HB light with 68K which is perfect with a 5mm blue LED bright enough but not blinding. The extra parts of the circuit feed 5 contacts which connect in the back of the speedo housing where you find the oil pressure buzzer of doom!!!! and it's related circuit board.
While I was in there I looked at the analogue clock which had stopped moving years ago. The later clock has only one electyrolytic capacitor of 100 uf 20v . This had burned out leaving scorch marks around one side of the case. I replaced this with a 100uf 35v capacitor as thats what I had in the drawer!!! I blew the dust out of the clock and put it back together , cleaned all the needles, cleaned the instrument faces and the insides of the perspex viewing glasses.
Wow, a working dashboard and a working clock!!!!
When I get time I will decipher the circuit incase anyone needs it. In the mean time I have a ready built hardwire board for the earlier dash cluster!!!!
123-jn Autohomes Komet 2.1 DJ AUTO 1989 (closed loop LPG pierburg 2E3)
- Citroen C4 Picasso 1.6 HDi
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Re: Instrument cluster wiring issues.

Postby CovKid » 14 Jan 2018, 08:48

Pretty much what I did then. More a case of following the tracks and replicating with wire. A few dabs of hot glue here and there help. The dash lights can be swapped out for 10mm LEDs - only needs very minor filing of bulb shields and push them in. I wired the LEDs so they are always lit with ignition on.
Roller paint your camper at home: for MP4 download.
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Re: Instrument cluster wiring issues.

Postby kevtherev » 14 Jan 2018, 09:20

Nice work!
I had my dash out recently and it gave me the opportunity to fix all the little niggles
2.1 DJ on pierburg + LPG
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