autobrake disarm after touch down

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autobrake disarm after touch down

Postby Tamas Csapka » 27 Jan 2007, 11:24

Tamás Csapka
Jan 12, 07 - 3:45 PM autobrake disarm after touch down

Hello! We have a difficult situation on our plane 737-300. Sometimes after touch down autobrake disarm light come on. We replaced autobrake control modul, wheel speed sensors and NLG air ground relay! If you have a good trick pls put to the forum!

Jan 12th, 2007 - 6:27 PM Re: autobrake disarm after touch down

Hello Tamas,

Follow your t/s guide, you will almost certainly find one of your autobrake pressure switches, located on the aft wheel well bulkhead, being faulty.
best regards

Tamas Csapka

autobrake disarm light after touch down

Postby bandit » 28 Jan 2007, 06:12

please try to check the 28 vdc and continuity check of the 4 microswitches throttle in the a/t microswitch pack in the e/e may be the bad microswitch contact

Postby Pete » 04 Feb 2007, 07:49

Hei ,Bandit for info there is 2ea micro switch pack assys M1693 and M1640 and only s1 and s2 in both switch packs are involved with the auto brake system.And if ther whould be a loss of 28v from c/b c583 you cuold not arm the autobrake at all.And an easy way to werify the a/t throttle functions is to perf an A/T Bite on the fmc cdu.

Postby SWA -700 » 20 May 2007, 15:14

Take the throttle levers one at a time and move them up and slam the down if the light goes out them that sitch pack is the issue
SWA -700
Posts: 1
Joined: 05 Feb 2007, 00:02
Location: MDW Chicago

Autobrake disarm after landing

Postby acsmisi » 27 May 2007, 21:56

Dear Tamas! The S1 switch (M1639) resistant at closed position (Connector D10646, contacts 7, and 8) was 360 Ohm instead of 0 Ohm! After replacement, and adjustment of the autothrottle microswitch pack assy, the problem is not appered. By reason of this problem the solenoid valve (in the V122 Autobrake modul) couldn't operate, and after 36 sec Autobrake Disarm Light was ON.
Best Regards from Misi Acs, Budapest, Aeroplex.
HI! I'm an Avionics on 737 CL & NG
Posts: 1
Joined: 27 May 2007, 21:37

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