voltage display

M-Primke · Сообщение 22 фев 2019, 15:41

I have installed my display and have in the display 0.9V.
I have already rewelded everything and measured everything and found no mistakes.
12V, GND, Ignition is also measured and fits.
Does one know the mistake ???

DRIVE2 · Сообщение 22 фев 2019, 15:48

Take photo on both side of main PCB in good quality.

M-Primke · Сообщение 22 фев 2019, 20:42

First, my car VW T5 2004 Highline
I read 12V via the Can Bus.
The Pictures
https://www.dropbox.com/sh/rf7flsgsa4ok ... TXP8a?dl=0

DRIVE2 · Сообщение 22 фев 2019, 21:11

Present not soldered resistor.

Currently it is soldered only on the one side...
Need put it in place and solder.

Sorry.

M-Primke · Сообщение 22 фев 2019, 22:00

Thanks for the answer.
And I thought I had made a mistake.....

What kind of resistance must be soldered in there?

DRIVE2 · Сообщение 22 фев 2019, 23:08

Resistanсe 3 KOhm on this PCB.

Resistor is present on PCB. But it soldered to only one point and "standing like a soldier".

M-Primke · Сообщение 23 фев 2019, 19:46

I have re-soldered and tested it.
Works perfectly.

Thanks again for the great help

DRIVE2 · Сообщение 24 фев 2019, 08:33

I have re-soldered and tested it.
Works perfectly.

M-Primke · Сообщение 25 фев 2019, 22:37

I'm going back .....
I've got 2 units, my running is perfect now, but with my friend, a VW T5 Lowline comes directly with the error message:
Control light
and when he drives off: release the handbrake
An idea where I made a mistake ????
Greetings from Norderney Germany

DRIVE2 · Сообщение 26 фев 2019, 09:18

Check connection of TrInput6 to Green socket pin 13. Check shorts to neighboring pins, what is connected to the correct pins, e.t.c.

M-Primke · Сообщение 26 фев 2019, 22:40

I found the mistake.....
Cables for Trinput 6 and 8 were soldered to 7 and 9....

DRIVE2 · Сообщение 27 фев 2019, 03:23

Cables for Trinput 6 and 8 were soldered to 7 and 9....

it happens...

I found the mistake.....

mmgherasim · Сообщение 23 мар 2020, 14:18

I installed my ColorMFA unit in my A4 B7 and immediately noticed the voltage to be kinda low, 13.1. I went to the alternator to measure and I had 14.1 with consumers (navi, climate control unit) running and at the battery I had 13.9. I calibrated the display but my curiosity is where did ColorMFA got the wrong info from? On Engine MVB I had the correct value of ~14.0.

DRIVE2 · Сообщение 24 мар 2020, 01:13

Measure the voltage at the cluster connectors.
The engine has nothing to do with it.

mmgherasim · Сообщение 24 мар 2020, 14:31

I found the issue: If you connect the 12V feed to the instrument cluster PCB near the GND point, it will show less voltage, but at the 12V PIN of the green connector, the voltage is higher and accurate.

DRIVE2 · Сообщение 24 мар 2020, 14:45

Because there is a diode between the connection point on the board and the connector (on the cluster PCB). The voltage drop across the diode is about 0.9-0.6V (depended by diode type).

mmgherasim · Сообщение 24 мар 2020, 15:44

I figured this is the cause and I moved the 12V wire to pin 2 of green connector and all good now. The instructions should say to use the pin from the connector for the 12V, instead of the point on the board, so we don't have to adjust the voltage in the calibration settings. I got scared when I first saw ~13.2V