HP 9872T Trouble Shooting

[husmann]

(06-10-2018 04:29 PM)cruff Wrote:  

(06-10-2018 02:11 PM)rprosperi Wrote:  The group [VintHPcom] is fairly active, and likely your best chance of finding someone with experience with one of these plotters.

I'm a member of that group also, I'll try to help out either place.

What happens when you follow the self test steps in the service manual section 2-23? Note that the self test switch in this section is internal, not the one on the back panel.

Thanks a lot for your offer. Here we go:

[2.23.a] Remove power from the plotter. ✔︎
[2.23.b] Remove all interface cables. ✔︎
[2.23.c] Open the plotter. ✔︎
[2.23.d] Apply power to the plotter. The plotter powers up with front panel LEDs “ENTER”, “OUT OF LIMIT”, “ERROR”, and “CHART LOAD” on and a y-axis motor buzzing very loudly (see http://www.huswelt.de/MoHPC/HP9872T_PowerOn.mp4).
[2.23.e] Set the self test switch S4-2 to the on position. I assume the on position is towards the front panel away from the fan. Setting switch S4-2 to the on position has no effect on front panel LEDs and y-axis motor.
[2.23.f] Press the Reset switch S5 pushbutton (red). While the reset button is pressed the y-axis motor stops buzzing but the front panel LEDs stay on. Releasing the reset button has no effect on the front panel LEDs but in most cases the y-axis motor starts buzzing again. Whether the y-axis motor is buzzing or not has no effect on the following results.
[2.23.g] The Self Test LEDs will flash sequentially as a lamp test. Total failure here: each and every self test LED stays off.
[2.23.h] Press the Continue switch S3 pushbutton (green). ✔︎
[2.23.i] The test will run … Even after waiting more than two hours the front panel LEDs stay on, the y-axis motor continues buzzing loudly (if not silenced in 2.23.f), and all self test LEDs stay off.

Thanks for your efforts.

Wolfgang