Motorola TIMEPORT 280, Service Manual

Page: 43 / 64

6881038B15 May 14, 2001 39
Level III Service Manual Troubleshooting
Troubleshooting Chart
Table 3. PF B58 Telephone: Level 1 and 2 Troubleshooting Chart
SYMPTOM PROBABLE CAUSE VERIFICATION AND REMEDY
1. Telephone will not turn on or stay on. a) Battery either discharged or
defective. Measure battery voltage across a 50 ohm (>1
Watt) load. If the battery voltage is <3.25 Vdc,
recharge the battery using the appropriate
battery charger. If the battery will not recharge,
replace the battery. If battery is not at fault,
proceed to b.
b) Battery connectors open or
misaligned. Visually inspect the battery connectors on both
the battery and the telephone. Realign and, if
necessary, either replace the battery or refer to
a Level 3 Service Center for the battery
connector replacement. If battery connectors
are not at fault, proceed to c.
c) Transceiver board assembly
defective. Remove the transceiver board assembly.
Substitute a known good assembly and
temporarily reassemble the unit. Depress the
PWR button; if unit turns on and stays on,
disconnect the dc power source and reassemble
the telephone with the new transceiver board
assembly. Verify that the fault has been cleared.
2. Telephone exhibits poor reception or
erratic operation such as calls frequently
dropping or weak or distorted audio. a) Antenna assembly defective. Check to make sure that the antenna pin is
properly connected to the transceiver board
assembly. If connected properly, substitute a
known good antenna. If the fault is still present,
proceed to b.
b) Transceiver board assembly
defective. Replace the transceiver board assembly (refer
to 1c). Verify that the fault has been cleared and
reassemble the unit with the new transceiver
board assembly.
3. Display is erratic, or provides partial or
no display. a) Mating connections to or from
transceiver board faulty. Remove rear housing from unit, check general
condition of flex connector if the flex connector is
good, check that the connector is fully pressed
down. If faulty connector, replace the transceiver
board assembly. If connector is not at fault,
proceed to b.
b) Transceiver board assembly
defective. Replace the transceiver board assembly (refer
to 1c). Verify that the fault has been cleared and
reassemble the unit with the new transceiver
board assembly.
4. Incoming call alert transducer audio
distorted or volume is too low. a) Faulty transceiver board assembly. Replace the transceiver board assembly (refer
to 1c). Verify that the fault has been cleared and
reassemble the unit with the new transceiver
board assembly.
5. Telephone transmit audio is weak.
(usually indicated by called parties
complaining of difficulty in hearing voice). a) Microphone connections to the
transceiver board assembly defective. Gain access to the microphone as described in
the procedures. Check connections. If connector
is faulty proceed to c; if the connector is not at
fault, proceed to b.
b) Microphone defective. Gain access to microphone. Disconnect and
substitute a known good microphone. Place a
call and verify improvement in transmit signal as
heard by called party. If good, reassemble with
new microphone. If microphone is not at fault,
reinstall original microphone and proceed to c.