Service Manual

MM-E 2072-09333-00
3-6
3-5.3 Troubleshooting Procedure
The purpose of the troubleshooting procedure presented in this Section is to rapidly return a defective
Micom-Z to service by replacing suspected modules:
a. Identify the closest description of the problem under “Problem Symptom” in Table 3-3.
b. Perform the required corrective actions listed under “Corrective Actions” in the table in the
order of appearance, until the problem is corrected.
If the replacement of an item (module, PCB, assembly) during the troubleshooting procedure
does not correct the problem, reinstall the original item before continuing to the next step.
c. After a trouble is isolated, follow the repair instructions given in para. 3-6.
d. After correcting the trouble and repairing the unit, repeat the performance checks in accordance
with para. 3-4.
Table 3-3. Troubleshooting Procedure
No. Problem Symptom Suspected Module(s)
1 Transceiver cannot be turned on
• LORD module
• HI POWER module
• CONTROL HEAD module
• INTERCONNECTION module (trunk version only)
2 No receive audio
• LORD module
• CONTROL HEAD module
• INTERCONNECTION module (trunk version only)
Check also the flat cables and the coaxial cables
connections
3 No RF transmit power but transceiver
switches to the transmit mode
• LORD module
• HI POWER module
• CONTROL HEAD module
• INTERCONNECTION module (trunk version only)
4 Low RF transmit power First try to calibrate the RF transmit power using the
RSS.
• LORD module
• HI POWER module
• TUNER module
5 Transceiver cannot be switched to
transmit mode by pressing the
microphone PTT
• LORD module
• CONTROL HEAD module
• INTERCONNECTION module (trunk version only)
• Microphone
6 No LCD backlight CONTROL HEAD module
7 Blank LCD screen
• LORD module
• CONTROL HEAD module
8 LCD displays jumbled characters
• CONTROL HEAD module
• LCD
9 POWER LATCH message appears
• HI POWER module (harmonic filter)
• LORD module