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Posts: 19
I like to use some off te LEDs on the overheadpanel of the 737 seperate from the switches
Not all of the LEDs are swiching the same time as the switches is moving.
For instance the EVT-OH-FUEL-PUMP-1-AFT PMDG EventID 69669 for the switch.
For the corresponding LED i try the settings form the offset mapping for PMDG737NGX list
0x645F size in bytes 2 and Mask value 0xFFFF.
But unfortunately it it does not working.
Is this possible or do what am i doing wrong.
And what is the correct solution.
2019-08-15 15:10
From: ETSI, Germany
Posts: 3087

Your in the right direction BUT you use a wrong logic !

In most cases a LED annunciator will show us the status of a function.... NOT the Status of a switch.

In a simple example we look at the Gear .... If you use the leaver for Gear Down then your Switch ( and also the Virtual switch) are in DOWN Position..... But this NOT tell us if the Gear is down ! Maby its still in transition.... Maby Gear is broke and wont go down or Maby a System prevent the gear from working ( high speed altitude etc).
Summary: A Switch Position (Whatever your Real switch OR the Virtual Swith in PMDG) is NOT usefull to controll a LED.... What we need here is a Offset that show us the STATUS from the Virtual LED or the STATUS from the virtual Function itself.

About your problem:
Input Offset is correct. But Output Offset is Wrong!


645F 2 BYTE x 2 FUEL_PumpAftSw(2)

THIS Offset show us just the Position of the Virtual switches. (SW means Switch)

For the corespondending "Low Press" Led´s the correct Offset is....

646C 2 BYTE x 2 FUEL_annunLOWPRESS_Aft(2)

(ANNUN means Annunciator)

ATTENTION: This Offset ( and many more) is COMBINED .... The "x2" Note means here 2 Single Offsets are in a row....
This is done if a Element is existing more then 1 Time in a cockpit ..... There exist also X3 Systems in Radios e.g.)

In case the Offset have 2 Byte and is "x2" we see this are 2 Offsets ( each one Byte)
Here it include the Information for the LEFT and RIGHT Fuel AFT Led´s.
The FIRST Offset is 646C 1 BYte INT (Boolean) and it controll Left LED.
The SECOND is 646D ( Simply add +1 in Hexadecimal) Also 1 Byte INT Boolean .... And this controll the Right LED.


Sumamry for PMDG:
1. Use if available always ANNUN Offsets instead of SW Offsets for your LEDs.
2. Split "x2" Offsets in 2 Configs.... One for each LED.

I Hope you be able to do this now youreself..... If not request for more help !
Good Luck !
2019-08-15 16:16
Posts: 19
Thank you fot the quick reply.
I used the wrong command the switch instead of teh LED.
I tested it andyes it works and also understend the BYTE x 2
2019-08-16 11:12