opening the drive door/lid of an RM03 ?

[Henk Gooijen]

Hello readers,
I cleaned the first of my RM03 drives today. The drive is quite clean
even after several years of no attention. Just a few spiders webs and
tiny dead spiders, and little dust.  I picked up this drive in Turin
Italy, together with Edward several years ago. I cannot remember doing
it, but the head lock pin was in the lock position.
After cleaning and a good inspection (I found a small metal bracket
piece next to the PSU output plugs, and have not found where it came
from!), I mounted a mains power plug to the drive cable. Massbus cable
is attached to the drive, the other end is not connected to anything.
After setting all circuit breakers ON (two inside the drive, two at the
rear side next to the running hours counter), I plugged the mains in
and switched mains on. I hear humming of the fans, so it seems OK.

However, this is my problem: the door latch stays locked, I cannot open
the lid. I want to open the lid to clean the inside of the drive bay.
After some reading (EK-RM023-TD-001_RM02_03_Tech_May78.pdf), I found
this in chapter 4.4 (page 4-7):

The initialize sequence starts with the receipt of a Massbus INIT
signal from either port A or B. This sequence is used to condition both
the adapter and drive circuits to a known reset state. The functional
block diagram for the initialize command is shown in Figure 4-5.
The Massbus INIT signal (whether coming from port A or B) clears the
AT A bit in the attention summary register in the IF module. In the CS
module, it is converted to the MBA clear signal which performs the
following:
1. Clears the enable search latch
2. Sets the on latch
3. etc.

So, do I understand this correctly that without an initial Massbus INIT
signal the lid remains locked?  Or has this RM03 drive a "lock issue"?
If somebody has an RM03 drive, is it possible to open the lid without
Massbus cables hooked to the RH70 or RH11 controller?  Is that Massbus
connection required + INIT command to unlock the lid?

I have not yet cleaned the other two RM03 drives, and I do not want to
apply power without cleaning and inspection! So, I cannot check whether
all 3 drives keep the lid locked.

I forgot to take the camera with me, but I will take pictures!

Thanks,
- Henk