Page 11 of 11

Re: Dashboard PCB Replacement (CJH Design)

Posted: 10 Apr 2026, 20:00
by The Hairy Camper
Some good news today, I managed to source a Diesel tachometer from a Jetta. Had some time to fiddle and test it with the latest PCB prototype this week and although it's not a perfect fit, it works!

I may have a go at swapping over the PCB from the Jetta tachometer into the T3 tachometer I have. If it works I should have a functioning factory tachometer on my T3.

Image

Image

Re: Dashboard PCB Replacement (CJH Design)

Posted: 11 Apr 2026, 07:09
by Aidan
hence no temp gauge :lol:
Still looks like a good option for the fix

Re: Dashboard PCB Replacement (CJH Design)

Posted: 11 Apr 2026, 12:29
by The Hairy Camper
Temp and fuel gauge are there (and functioning!), but are not much good as they are hidden behind the Jetta RPM plate :lol:

A win is a win though!

Re: Dashboard PCB Replacement (CJH Design)

Posted: 24 Apr 2026, 14:07
by The Hairy Camper
I made some more progress this week. The factory petrol tachometer has now been converted to work with my diesel van. The red line is different, but the revs seem to match my aftermarket tach very closely.

Image

Image

Also, I felt bad about taking apart my Jetta tachometer, so I decided to try out these tachometer PCB's I had made. Turns out they work! I've also figured out how to bench test them with a signal generator now too, which makes calibrating them much easier.

Image

Image

I still have some more ideas/changes I would like to make, but I'm pretty happy with the progress.

Re: Dashboard PCB Replacement (CJH Design)

Posted: 17 May 2026, 09:29
by JeffRoo
If of interest I have found the booklet that came with the CJH design I bought a few years back. I could scan it and send. Not sure of CJH IP though.
Anyway, the offers there if needed.

Re: Dashboard PCB Replacement (CJH Design)

Posted: 17 May 2026, 09:32
by TwinTurbo
is it different to the already posted info?

Re: Dashboard PCB Replacement (CJH Design)

Posted: 17 May 2026, 13:12
by JeffRoo
Good catch, no it’s not. It’s the same as the pdf

Re: Dashboard PCB Replacement (CJH Design)

Posted: 10 Jun 2026, 12:53
by The Hairy Camper
Some more updates.

A new connection for aftermarket tachometers has been included on the Dashboard PCB. Much easier to connect now and no need to tamper with old wiring.

The combined tachometer PCB had some connection issues working with the temperature and fuel gauge. This got upgraded and is working much better now.

Oh, and I decided to see how purple looked for the PCB's :lol:

Image

Original and aftermarket Tachometers working simultaneously. Unnecessary, but looked very interesting to watch.
Image

Image

The work continues.

Cheers

Re: Dashboard PCB Replacement (CJH Design)

Posted: 10 Jun 2026, 14:03
by TwinTurbo
I colour code my pcb's based on lifecycle. Although I can't remember the sequence it's on my office monitor. Never use white as it screws with the silk screen and capacitors end up inverted.

Re: Dashboard PCB Replacement (CJH Design)

Posted: 04 Jul 2026, 11:08
by firetrader
A new dashboard or revamped /renewed circuitry is on my hit list, the ribbon on the rear of mine is quite tatty, it is working ok though for now, however, if in the future I see a recommended fix I would be interested as I honestly couldn't try myself as I know I would mess it up, through the years on this form I have seen the odd post covering this, but as I say, some people fix it themselves, would only try it if it was a simple plug in. The photo below looks like its like that, but as I say mine does work (for now).Hope yours is good now?