Broadcast Electronics AM-2.5E, User Manual

Page: 254 / 320

WARNING: DISCONNECT POWER PRIOR TO SERVICING
2-11
TABLE 2-3. CONTROLLER CIRCUIT BOARD TROUBLESHOOTING
(Sheet 2 of 2)
SYMPTOM CIRCUITRY TO CHECK
NO TRANSMITTER ON SIGNAL 1. Check for a HIGH at U23A pin 3.
OUTPUT A. If the HIGH is present, defective Q13.
B. If the HIGH is not present, check for a LOW
at U23A pin 2.
1. If the LOW is present, defective U23A.
2. If a HIGH is present, contact the
Broadcast Electronics Customer Service
Department.
CONFLICT INDICATOR 1. Check U7, U8, U9, S1, S2, S3, U12A, U12B,
ILLUMINATED U21A, U21B, U21C, U20A, U20B, U20C, U20D,
U19, and U13.
TABLE 2-4. ECU POWER SUPPLY TROUBLESHOOTING
SYMPTOM CIRCUITRY TO CHECK
NO OUTPUT POWER 1. Check the ECU power supply fuse.
NO NORMAL/FAULT 2. Check the ECU power supply assembly.
ECU INDICATIONS
2-69.
COMPONENT REPLACEMENT PROCEDURE.
Component replacement procedures for
the ECU assembly circuit boards are presented in PART I SECTION V. Refer to
COMPONENT REPLACEMENT in SECTION V as required for the replacement
procedures.