View Full Version : B737 "elec" Light
I'd like to share with you a trick I learned the hard way yesterday, as it is not documented and not provided to (our) crews.... :mad:
After eng start, the "ELEC" light illuminated on the digital panel (we only have a couple of airplanes - I'm talking classics here - with this kind of ammeters...).
It can illuminate only on the ground, and means a fault in the stby power... so a guy who doesn't know the trick will go back and call a qualified engineer.... :mad:
The trick is: place both meter selectors to TEST (I still don't know if both are needed, or which of the two is enough...), and hold down the MAINT Test Switch.
You will get a display in sequence of the stored faults, then the f*****g ELEC light will go off!
:ok:
LEM
Rainboe
6th Mar 2005, 18:36
Why the expletive? Does it serve a function?
LEM - this is a QRH item on any 737-400 fitted with the elec panel, and very much as you describe it - but without the expletives. 'Old hat' to those who operate the aircraft.
The correct drill is:
Select 'TEST' on both
MAINT BUTTON - press and release.
After fault display,
MAINT BUTTON - press and release.
If message 'Hold button Clear Faults'appears,
MAINT BUTTON - push and hold.
If message ' Faults cleared' appears, OK
IF NOT, AND 'ELEC' light STAYS ON - DO NOT TAKE OFF
Quite common after a ground air start, and often can be avoided by selecting ground power OFF before connecting the engine gens after start.
We also suggest you post ALL 737 items in one post, unless, of course, you are after the posting record, or maybe there is more than one 'LEM'?:D
Global Pilot
6th Mar 2005, 19:10
"Why the expletive? Does it serve a function?"
The ELEC light becomes the FFFFing ELEC light when it comes on after start!
FlightDetent
6th Mar 2005, 20:41
You see that, some get those lovely dual batteries, on-demand APU, F/O nosewheel, funny COM selector thingy, audio transfer switch equipped machines only as pre-owned. Thus the expertise takes some time to develop. Indeed it is these aircraft with digital ELEC panels we are talking about? :suspect:
Furthermore to what LEM describes we've learned that this light does not indicate a malfunction in progress so to speak but rather is a inidcation of a trouble whilst selecting main generators on-line. At first, is not a no-go item, wheteher you clear the indication or not makes no difference anyhow. Secondly, this indication comes up only and always with APU inop for various electrical transfers during the crosbleed start procedure. With proper APU bus supply, no tricks whatsoever.
Correct?
'evening...
FD
IFixPlanes
6th Mar 2005, 22:20
Here are the Data for the 737CL with the digital Elec.Control Panel
The ELEC light will come on for these fault messages:
► STAT INV INOP
► BAT CHGR INOP
► GEN1 FAULT
► GEN2 FAULT
► STBY BUS XFER FAULT
► BAT BUS XFER FAULT
► INTERFACE FAILURE
The Maintenance Messages will be removed when the RECALL/TEST button
is pressed and held for approximately 6 seconds.
NOTE : Except for the Generator No. 1 and No. 2, the faults cannot be cleared
by the MAINT button when the fault condition still exists.
Ingo
FlightDetent
7th Mar 2005, 07:04
Now I'm puzzled...
You see that, some get those lovely dual batteries, on-demand APU, F/O nosewheel, funny COM selector thingy, audio transfer switch equipped machines only as pre-ownedsounds as if you have one of my second-hand machines :D PS Never raced or rallied...............................
If you PM me the current reg I'll be able to give you some history.
Regarding the 'Ingo' input, in my experience the fault was normally the standby Xfer, and nearly always on air starts, and ALWAYS cleared, so do not be 'confused'. Try my 'trick', as taught to me:D
BOAC,
G-DOCD/I went to the Czech Republic so it does seem likely that its one of the oldies...
Bumblebee
7th Mar 2005, 11:45
BOAC..
Hi there..
Quite common after a ground air start, and often can be avoided by selecting ground power OFF before connecting the engine gens after start.
Works the same if you select the Generator of the donkey you've just started onto the bus, then select the ground power switch off to drop that off the other bus - before the ramp crew disconnect the GPU.
Otherwise doesn't it go dark and dump everything you've put in to the FMC?? ;)
99% of the time the Elec light is due to Stby Bus transfer fault when the Ground power drops off instead of being selected off.
Probably right, BB - haven't flown them for a while:D
BOAC, our QRH goes like that:
Condition: The ELEC light illuminated indicates a fault exists in the DC or standby power system.
Note: The ELEC light only illuminates on the ground.
End of the checklist.
That's all we have. That's why I asked.
Re the remark about posting all the 737 stuff together:
sorry, but it makes much more sense to me to keep them separated. Much more clear. We concentrate on one thing at a time.
Me being after the posting record?
I am childish at times, but not that much!!
And it would be quite difficult to do that, now that the number of posts has been removed from the profile of supporting ppruners...;)
LEM - that sounds like a NG QRH? I have never had the light on in a NG so I do not know if the procedure works. The NG QRH DOES kind of leave you 'up-in-the-air' on the ground, I agree:D
I don't know, BOAC, we are flying classics and that's what the company gave us... :confused:
Btw, I can confirm that happened to me with the APU inop, exactly as you mates described...
Amazing, I always learn a lot discussing stuff here :ok: , and thanks to Bumblebee for his tip about selecting the engine gen on and dropping the ground power BEFORE it is disconnected!
:D LEM