Tait TM8000 Series, Service Manual

Page: 119 / 244

TM8100 Mobile Radio Service Manual Servicing Procedure 119
May 2004 © Tait Electronics Limited
TRANSMIT AND TRANSMIT-AUDIO FAULTS — PARTS 1 AND 2
1. Initial checks
(1) If the radio fails to transmit, exchange the microphone for a serviceable spare
microphone.
(2) Check if the radio transmits.
(3) If the radio transmits, the original microphone is faulty; go to (4). If the radio still fails
to transmit, reconnect the original microphone, and go to (5).
(4) Repair the faulty microphone as described in the accessories manual, and return to
Step 4 of Task 7.
(5) Detach the control head as in Subsection 6.1 (on page 127) , and exchange it for a
serviceable spare control head.
(6) Check if the radio transmits.
(7) If the radio transmits, the original control head is faulty; disconnect the spare control
head, and go to Part 2 below. If the radio still fails to transmit, the radio body is faulty;
reconnect the original control head, and go to Part 3 in Figure 5.6.
2. Control head faulty
(1) If the control-head loom has already been checked, go to (5). If it has not, exchange
the loom for a serviceable spare loom.
(2) Check if the radio transmits.
(3) If the radio transmits, the original loom is faulty; go to (4). If the radio still fails to
transmit, reconnect the original loom, and go to (5).
(4) Replace the faulty control-head loom, and return to Step 4 of Task 7.
(5) Check the control-head connector and microphone connector on the control-head
board and the path between them.
(6) If either connector is faulty, remove the control-head board as in Subsection 6.2
(on page 131) , and replace the connector. If there is an obvious fault causing a break
in the path between the connectors, repair it. If no fault can be found, replace the
control-head board as in
Subsection 7.4 (on page 163) .
(7) Check if the radio transmits.
(8) If the radio transmits, return to Step 4 of Task 7. If the radio still fails to transmit, re-
assemble the control head with the original control-head board, and return to Step 4
of Task 7.
Figure 5.5 Chart for locating and rectifying faults that affect the transmit function — control head
is faulty