FLC OF AN MLG ABORTED TKOF DUE TO THE TKOF WARNING HORN SOUNDING WHEN THE THROTTLES WERE ADVANCED. LATER FOUND TO BE CAUSED BY THE SPD BRAKE LEVER BEING RAISED SLIGHTLY OUT OF THE DETENT WHEN THE ENG WAS CYCLED INTO AND OUT OF REVERSE AFTER ENG START DUE TO A REVERSER LIGHT ILLUMINATING.

Narrative

AFTER ENG START; THE #2 'REVERSER' LIGHT ILLUMINATED ON THE OVERHEAD PANEL. WE ACCOMPLISHED THE IRREGULAR PROC WHICH BASICALLY SAYS TO CONTINUE AS LONG AS THE 'REVERSER UNLOCKED' IS NOT ALSO ILLUMINATED. I CYCLED THE ENG INTO AND OUT OF REVERSE IN AN ATTEMPT TO PUT OUT THE LIGHT; AND IT DID GO OUT AFTER A MIN. WHEN WE BEGAN THE TKOF ROLL; THE TKOF WARNING HORN SOUNDED WHEN THROTTLES WERE ADVANCED. I IMMEDIATELY ABORTED THE TKOF AND NOTIFIED TWR AND PAX. AFTER CLRING THE RWY; WE VERIFIED THAT PARKING BRAKE; SPD BRAKE LEVER; TRAILING AND LEADING FLAPS AND STABILIZER TRIM WERE IN THE CORRECT POS FOR TKOF. EVERYTHING LOOKED NORMAL ALTHOUGH THE FO OBSERVED THAT THE SPD BRAKE LEVER LOOKED LIKE IT MAY HAVE BEEN RAISED SLIGHTLY. IT WAS FULLY FORWARD IN THE 'DOWN' POS BUT NOT LOWERED INTO THE DETENT. I TESTED THE TKOF WARNING HORN AND IT APPEARED TO OPERATE NORMALLY. MAINT AND DISPATCH WERE NOTIFIED AND THE SUBSEQUENT TKOF WAS UNEVENTFUL. LATER IT BECAME CLR TO ME WHAT CAUSED THE TKOF WARNING HORN: CYCLING THE ENG INTO AND OUT OF REVERSE ACTIVATED THE AUTO SPOILER SYS WHICH RAISED THE SPD BRAKE LEVER 1/8 INCH OUT OF THE DETENT. OUR SOP INCLUDES VERIFYING THAT THE LEVER IS DOWN AND TESTING THE TKOF WARNING HORN DURING EACH COCKPIT PREPARATION; BUT I WILL NOW CHK THESE AGAIN IF I HAVE A REVERSER IRREGULARITY BEFORE TKOF.