A B737-300 CREW RPTS A FLICKERING MASTER CAUTION LIGHT OF UNKNOWN ORIGIN DURING TKOF LEADING TO A HIGH SPD REJECTED TKOF.

Narrative

AFTER BEING CLRED FOR TKOF (FO WAS THE PF) AND AT 80 KTS; CAPT (PNF) NOTICED A MOMENTARY FLICKER OF THE GLARE SHIELD MASTER CAUTION LIGHT. THERE WAS NO ASSOCIATED '6 PACK' CAUTION LIGHT ON; NO FORWARD PANEL LIGHTS ON. CAPT TOOK A QUICK GLANCE OF OVERHEAD PANEL -- NO LIGHTS WERE ILLUMINATED. AS CAPT'S EYES CAME BACK FORWARD; MASTER CAUTION LIGHT AGAIN BLINKED WITH NO '6 PACK' LIGHTS ILLUMINATED. CAPT INITIATED ABORT APCHING 100 KTS. REJECTED TKOF BRAKING ENGAGED. WITHIN A COUPLE OF SECONDS; IT WAS CLR THIS WOULD BE AN UNEVENTFUL CTLED STOP; CAPT ENGAGED BRAKES TO RELEASE REJECTED TKOF BRAKING. ACFT COASTED TO AN UNEVENTFUL STOP AND EXITED THE RWY. CAPT ATTEMPTED TO CREEP ALONG ON THE PARALLEL TXWY TO FACILITATE BRAKE COOLING. FO CONFIRMED (WITH THE FLT MANUAL) BRAKE COOLING TIME OF APPROX 50 MINS (AND NOT IN THE CAUTION ZONE). R ENG WAS SHUT DOWN TO FURTHER MINIMIZE BRAKE USAGE. ACFT RETURNED TO THE GATE WHERE IT WAS CHOCKED WITHOUT SETTING THE PARKING BRAKE. DISPATCH; MAINT; AND THE FLT OPS DUTY OFFICE WERE SUBSEQUENTLY NOTIFIED. UNFORTUNATELY; IN THE NECESSARY MOMENTS TO DETERMINE THE GO/NO-GO DECISION; WITHOUT SECONDARY MALFUNCTION LIGHTS; CREW WAS UNABLE TO ASCERTAIN THE SERIOUSNESS OF THE MALFUNCTION RESULTING IN AN ABORT DECISION SLIGHTLY ABOVE 80 KTS. WHILE TAXIING BACK; CREW WAS ABLE TO DETERMINE THE ACTUAL CULPRIT WAS A FLICKERING (MOMENTARY) EQUIP COOLING 'OFF' LIGHT. SAID SWITCH WAS IN THE 'NORMAL' POS. ADDITIONAL SALIENT INFO: AMBIENT TEMP AT SLC WAS 38 DEGS C (100 DEGS F). FIELD ELEVATION WAS 4227 FT. SAID ACFT HAD THE APU BLEED VALE INOP'ED IN THE CLOSED POS. ACFT WT WAS APPROX 114000 LBS; WITH A NEARLY FULL PAX COMPARTMENT. PERFORMANCE DATA REQUIRED A BLEEDS OFF; UNPRESSURIZED TKOF. NEEDLESS TO SAY; ADEQUATE COOLING AIR WAS NOT AVAILABLE PRIOR TO TKOF. THIS COULD VERY WELL HAVE BEEN A CONTRIBUTING FACTOR.