e39 HD44780 24x2 to cluster

[bumer36]

Hi All,
Was looking for a long time for this and couldn't find literally anything.

In order to solve the problem with the cluster LCD "dead pixels" due to flex ribbon failure, I've got an idea to integrate the HD44780-based 24x2 LCD instead, soldering it to the corresponding signals on board Hitachi controller.




Here's the progress.








... 4 data lines (D4-D7) either 8 data lines connected (D0-D7) -- the same result...




On any display output only a few first characters being displayed. The rest is static, always the same after initialise procedure.

Test #2:







All wires are ok, no shorts (otherwise I would see the difference on stock display as well).
As far as I discovered, the onboard LCD is driven by parallel interface without any shift-registers or i2c or SPI bus.
I was also thinking to attach Arduino to the display for the correct initialisation process and then switch its data and signal lines back to the cluster controller with transistor keys (too much work for me, not now).

Any ideas on how this cluster initialises its own LCD? My initial guess was that it should have be a normal 2-lines LCD.

[bumer36]

Seems like no one is interesting in this.

- - - Updated - - -

My bad. Wrong category.

[bumer36]

Dear admins, could you please move it to the appropriate category? Can't find how to.
Thanks!