Replacing the dashboard plastic PCB

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

CJH wrote:
Version 0.4 is still the most up-to-date version that I have. But it does need some additions (mostly around the DOPS option) and some corrections as spotted by various kind people.

While I'm still working on an update to the guide, I thought it might be useful to show the details of the DOPS option, to save me retyping it for everyone that I send a kit to.

There are two main points:
1) the orientation of the ribbon cable and the corresponding pins on the back of the speedo
2) the need to omit resistor R3

1) Cable and socket orientation
When soldering the 2x3 box header, note that the socket is keyed so that the DOPS cable can only go one way round. There is also a numbering convention for the pins, with the location of pin 1 being indicated by a small triangle on both the plug and socket.

Image

You'll also see that the PCB itself has a small number '1' to indicate which is pin 1. Because of the way that I've assembled the plug onto the ribbon cable, you should therefore aim to solder the box header such that the keyway gap is on the right hand side, closest to the edge of the PCB.

Image

If you do it this way, you'll find that the ribbon cable exits the plug in the direction of the speedo pod.

Image

The colours of the ribbon cable aren't significant - they're different for every kit, as I just peel off the next 6 strands. But the important thing is that whichever strand is at the bottom of the ribbon (blue in the above photo) is pin 1, and pin 1 should connect to the leftmost pin in the speedo - the others then just connect in sequence. The photo below shows this. By routing the cable up the side of the speedo pod, then turning it through 90 degrees (with a 45 degree fold - the photo explains this better!), the pins should naturally fall in the right positions.

Image.

2) Resistor R3
When assembling the components, you should OMIT resistor R3, since the current to the OIL LED is controlled by the DOPS circuit board. Soldering R3 in place would put that LED under the joint control of the 0.3bar pressure switch and the DOPS circuit, which would probably cause problems.
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

Bandage
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Re: Replacing the dashboard plastic PCB

Post by Bandage »

Hi

How do I order one of these kits, just found the instruction manual online and discovered this is exactly what I need
Thanks

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

Bandage wrote: How do I order one of these kits...

Send me a PM. The options are:

1) A 'bag of bits' for self-assembly. £30, including first class postage within the UK. Postage elsewhere may cost a little more. Requires basic soldering skills.

2) A 'built-to-order' board, for those who prefer not to tackle the soldering. £62.50, including first class postage within the UK. If you decide to go with this option, I have a standard list of questions about your requirements, which I can send when needed.

3) An add-on 'low fuel warning light' PCB, to make use of a spare LED on the dash PCB. There's a thread about it here. £4.50 if posted with a dash PCB, or add another £1 if it's posted separately. I'll build this board at no extra cost if you're not keen on doing the soldering.

I have a couple of the dash kits left, but I'm temporarily out of stock of the low fuel kits at the moment. I'll have new stocks of everything in just over a week's time.

Chris
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

Dash kits and low fuel kits are available again. I ordered plenty of PCBs this time, and I've been accumulating various other parts too - should keep me going for quite a while.

Image
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

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garyd
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Re: Replacing the dashboard plastic PCB

Post by garyd »

My son & I have been assembling our unit today and have a couple of questions for those who have built these units for late diesel dash's. (Those with tachometers and DOPS)

We have found that the three wire ribbon (red, orange, brown) for the tachometer connection is too short to reach the screw connection block on the pcb. Has anyone else found this?

With regard to these connections we believe that the pins on the tacho are:
pin 1 - ground/earth
pin 2 - missing
pin 3 - ignition live
pin 4 - is the 'W' feed via pins 4 & 9 in the 14 pin edge connector and the right hand end position on the upper screw connector block.
Presumably the earth & live wires can be doubled into any suitable position in the same screw block?

There is a 2 core flylead to power the digital clock. Can anyone advise on the polarity of the clock terminals, please? That is, is the positive terminal the left or right pin?

Thanks and best wishes for a happy Christmas,
Garyd

1990 Transporter syncro camper
2 litre AGG 'GTi' engine

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

Hi Gary

I'll send you a PM. Wrapping first!
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

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garyd
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Re: Replacing the dashboard plastic PCB

Post by garyd »

OK I have sorted the clock polarity - by the simple (once remembered!) method of using a multi-meter on the foil PCB.

Once I'd overcome the issue of a broken track just back from the edge connector section I was able to detect links from the clock plug to pins 3 (ground) & 5 (clock).

So, looking at the back of the clock with it in position (socket above lamp) the negative (ground) is on the right and the constant live feed on the left.

We also sorted the short leads by splicing on additional lengths of similarly weighted & coloured wire.

Might find time in the next couple of days to test it in-situ and find out if it all works.

I am also installing a new digital clock face at the same time and tried testing that before removing the foil PCB but it didn't work! However, since the power track was broken I am hopeful it will work on the new wiring.

Happy Christmas and best wishes for a blessed new year
Garyd

1990 Transporter syncro camper
2 litre AGG 'GTi' engine

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3cylinders
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Re: Replacing the dashboard plastic PCB

Post by 3cylinders »

Have just fitted to a late petrol, analogue clock with DOPS and have:

1. No needle movement on the the temp gauge, though the warning LED comes on and goes out when starting.
2. The oil LED flicks on and off when turning the ignition to power, does not come back on.
3. The battery LED comes on at ignition power, goes out on starting as expected, LED glows very faintly for a while in a cyclical nature, so faint, it is still barely visible at night.

I have some testing to do, but any recommendations on tests would be appreciated and guidance on how to work out if C2 and C3 are required - neither are fitted.
R3 is also not fitted.
On my pod, the clock housing has a 'rod' running along the underside of the rear of the clock housing - had to cut part of this away to fit the low fuel warning board - I'll get a photo when I take the pod out again.
On the plus side, it looks like my starter solenoid 'click, click, click...start' is now sorted - just as well, my next swap out was going to be the starter and the fuel gauge responds faster on startup.

On closer inspection of my original PCB and comparison with Chris' manual v0.4, I have pins 4 and 6 bridged on the flexi with no track off pin 6 - the text is as follows, so I'll verify my wiring order first.

01. Instr.Bel.
02. Fernlicht
03. Allgem
04. Frei(temp)
05. Uhr
06. Temp
07. Tank
08. + Allgem
09. KL.1
10. Blinkerkontr
11. Ladekontr
12. 1.8 bar
13. 0.3 bar
14. Diesel/Oxs/Cat
1991 1.9 DG Petrol Bus manual transmission

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garyd
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Re: Replacing the dashboard plastic PCB

Post by garyd »

Right, we connected up the dash this morning and tested everything. All fine except that the DOPS/B of D sounded above 2krpm! It is just possible that this was happening before but I have had a tiny piece of card between the oscillating contacts to 'silence' it for some time (since I had a cable snap in the engine bay whilst away.)

Checked through wiring at engine end and found no faults. Eventually traced fault to a disconnect between contact 12 of the 14 pin connector and the new edge connector. Contacts in the old 14 pin had got pushed back and failed to touch the new gold contact. Re-shaped the sprung contacts and now all is well!

We have selected the two red LEDs for the battery & oil lamps and these are pretty bright in the current murky weather. However, you do need to notice them if they come on, even in the brightest conditions, so should be fine in normal use.

Chris, I have taken several photos of the back of the dashpod with the new pcb & wiring if you need them for your revised instruction manual? Let me know. I can't post them here as I don't run an appropriate photo hosting account. Thanks again for all your efforts putting this package together.

Happy new year to everyone.
Garyd

1990 Transporter syncro camper
2 litre AGG 'GTi' engine

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3cylinders
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Re: Replacing the dashboard plastic PCB

Post by 3cylinders »

Sorted 1 and 2
3 - No longer cyclical but permanent, although needs failing daylight to detect.
̶1̶.̶ ̶N̶o̶ ̶n̶e̶e̶d̶l̶e̶ ̶m̶o̶v̶e̶m̶e̶n̶t̶ ̶o̶n̶ ̶t̶h̶e̶ ̶t̶h̶e̶ ̶t̶e̶m̶p̶ ̶g̶a̶u̶g̶e̶,̶ ̶t̶h̶o̶u̶g̶h̶ ̶t̶h̶e̶ ̶w̶a̶r̶n̶i̶n̶g̶ ̶L̶E̶D̶ ̶c̶o̶m̶e̶s̶ ̶o̶n̶ ̶a̶n̶d̶ ̶g̶o̶e̶s̶ ̶o̶u̶t̶ ̶w̶h̶e̶n̶ ̶s̶t̶a̶r̶t̶i̶n̶g̶.̶
̶2̶.̶ ̶T̶h̶e̶ ̶o̶i̶l̶ ̶L̶E̶D̶ ̶f̶l̶i̶c̶k̶s̶ ̶o̶n̶ ̶a̶n̶d̶ ̶o̶f̶f̶ ̶w̶h̶e̶n̶ ̶t̶u̶r̶n̶i̶n̶g̶ ̶t̶h̶e̶ ̶i̶g̶n̶i̶t̶i̶o̶n̶ ̶t̶o̶ ̶p̶o̶w̶e̶r̶,̶ ̶d̶o̶e̶s̶ ̶n̶o̶t̶ ̶c̶o̶m̶e̶ ̶b̶a̶c̶k̶ ̶o̶n̶.̶
3. The battery LED comes on at ignition power, goes out on starting as expected, LED glows very faintly for a while in a cyclical nature, so faint, it is still barely visible at night.

It was the fit of the PCB strip to the VW 14 pin connector - one side of Chris' board slots into a groove on one side but sits inline with a projection on the other - I had it to one side of the projection and pins 6 and 11 of the VW connector were sliding in the white plastic housing - found it by chance when the battery / alternator light went out while moving the cable run from the main PCB board to one side.
1991 1.9 DG Petrol Bus manual transmission

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

garyd wrote:
We have selected the two red LEDs for the battery & oil lamps and these are pretty bright in the current murky weather. However, you do need to notice them if they come on, even in the brightest conditions, so should be fine in normal use.

Chris, I have taken several photos of the back of the dashpod with the new pcb & wiring if you need them for your revised instruction manual? Let me know. I can't post them here as I don't run an appropriate photo hosting account. Thanks again for all your efforts putting this package together.

Hi Gary

I'm glad you've got it all working, and photos would be great, thank you. If you need a reminder of my email address I can PM it to you.

Yes, the two red LEDs are naturally bright (rated at 400mcd), and even with the supplied 3k9 Ohm resistors, meaning that they're only getting ~3mA (instead of the ~25mA provided by the 470 Ohm used with the originals) they are still a bit brighter than the originals. But like you I reasoned that after starting the engine they'll only come on when they need to be seen instantly, in any light.

My apologies for the short tacho lead. I think I posted your kit a while ago, before I realised that it needed to be longer. I now supply the 3-way tacho ribbon and the 2-way clock ribbon as a single 40cm 3-way ribbon with terminals on both ends, so that you can cut a 3-way piece that's long enough for the tacho, then peel one strand off what's left and use the remaining 2 strands for the clock. If you remind me of your address I'll pop a new 3-way ribbon in the post to you.
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

3cylinders wrote:Sorted 1 and 2
3 - No longer cyclical but permanent, although needs failing daylight to detect.
̶1̶.̶ ̶N̶o̶ ̶n̶e̶e̶d̶l̶e̶ ̶m̶o̶v̶e̶m̶e̶n̶t̶ ̶o̶n̶ ̶t̶h̶e̶ ̶t̶h̶e̶ ̶t̶e̶m̶p̶ ̶g̶a̶u̶g̶e̶,̶ ̶t̶h̶o̶u̶g̶h̶ ̶t̶h̶e̶ ̶w̶a̶r̶n̶i̶n̶g̶ ̶L̶E̶D̶ ̶c̶o̶m̶e̶s̶ ̶o̶n̶ ̶a̶n̶d̶ ̶g̶o̶e̶s̶ ̶o̶u̶t̶ ̶w̶h̶e̶n̶ ̶s̶t̶a̶r̶t̶i̶n̶g̶.̶
̶2̶.̶ ̶T̶h̶e̶ ̶o̶i̶l̶ ̶L̶E̶D̶ ̶f̶l̶i̶c̶k̶s̶ ̶o̶n̶ ̶a̶n̶d̶ ̶o̶f̶f̶ ̶w̶h̶e̶n̶ ̶t̶u̶r̶n̶i̶n̶g̶ ̶t̶h̶e̶ ̶i̶g̶n̶i̶t̶i̶o̶n̶ ̶t̶o̶ ̶p̶o̶w̶e̶r̶,̶ ̶d̶o̶e̶s̶ ̶n̶o̶t̶ ̶c̶o̶m̶e̶ ̶b̶a̶c̶k̶ ̶o̶n̶.̶
3. The battery LED comes on at ignition power, goes out on starting as expected, LED glows very faintly for a while in a cyclical nature, so faint, it is still barely visible at night.

It was the fit of the PCB strip to the VW 14 pin connector - one side of Chris' board slots into a groove on one side but sits inline with a projection on the other - I had it to one side of the projection and pins 6 and 11 of the VW connector were sliding in the white plastic housing - found it by chance when the battery / alternator light went out while moving the cable run from the main PCB board to one side.

Hi Simon

Good to hear that you've fixed those two problems. The edge connector was designed to be a fairly tight fit, but I bought some spare multiplugs for testing purposes and I did find that there's a bit of variation between them - the edge connector is tighter in some than in others.

Regarding the faintly glowing battery light, I did experience that myself with my first version of the board, and I suspect there is somehow a tiny residual current in that circuit. I'm not really sure how that can be though, since the positive side is the ignition voltage, and the 'negative' side is the blue exciter wire, which should also be at ignition voltage once the engine is running. There's a diode between them - maybe that plays a part. But I believe that tiny current is enough to get the 400mcd red LED to glow a bit, albeit very dimly. Can I check which resistor you've fitted in R4? In my experience, the 3k9 resistor supplied was enough to kill that faint glow, but maybe there's something different about that circuit in your van that means a slightly higher value might be needed.
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

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CJH
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Re: Replacing the dashboard plastic PCB

Post by CJH »

3cylinders wrote: On my pod, the clock housing has a 'rod' running along the underside of the rear of the clock housing - had to cut part of this away to fit the low fuel warning board - I'll get a photo when I take the pod out again.

Yes please - a photo would be useful.
"I'm a man of means, by no means....King of the Road!"

1983 Viking Xplorer, 2.1DJ

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3cylinders
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Re: Replacing the dashboard plastic PCB

Post by 3cylinders »

Hi Chris,

Re the resistor in R4, - it is 3k9

Edited - better images of rod on clock housing
Image
Image
1991 1.9 DG Petrol Bus manual transmission

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3cylinders
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Re: Replacing the dashboard plastic PCB

Post by 3cylinders »

Hi CJH,

What was the company you used for printing the boards and do you know the minimum order value / quantity ?

Thanks,
1991 1.9 DG Petrol Bus manual transmission

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