What was found
(CAN) ALT CHARGING SYS WOULDN`T COME ONLINE. TROUBLESHOOTING SHOWED EVERYTHING SHOULD BE WORKING. ALL VOLTS ( IAW MM) APPEARED TO BE NORMAL, CHARGING SYS SHOWING A DISCHARGE. ALT CONTACTOR IS IN SERIES WITH MAIN BUSS & BATTERY. CURRENT NOT FLOWING THROUGH CONTACTOR, ALT FAILED TESTS. HIGH RIPPLE VOLTS DETECTED & FAILURE OF ALT OCCURED. INSTALLED NEW ALT & CONTACTOR VOLTAGE, NO CURRENT. SHUTDOWN SYS. VOLT CHKD AT OUTPUT SIDE OF ALT CONTACTOR & FOUND NORMAL. NO CURRENT FLOW. REPLACED ALT CONTACTOR & SYS BEGAN TO OPS CHK OK. 2ND CONTACTOR FAILURE, TOOK 1ST FAILURE, SPLIT OPEN CONTACTOR. CONTACT POINTS DISCOLOURED & CONTACT POINTS BLACK (CARBON BUILD UP) POSSIBLE CURRENT LOAD THROUGH CONTACTOR TOO HIGH.