Motorola 880 Service Manual page 50

Dual Band 880/890 (DCS/GSM)
Table 8: GSM Logic/Processing Troubleshooting and Repair Chart
Logic/Processing
Symptom
5. Hinged mouth-
piece does
not go on/off
hook correctly.
6. Vibrator
feature not
functioning.
6. Vibrator
feature not
functioning.
42
Probable Cause
b) Magnet in flip defective.
c) Keypad/Display board
defective.
d) Logic/RF Board Assembly
defective.
a) Vibrator motor defective.
c) Logic/RF Board Assembly
defective.
68P09403A50
Verification and Remedy
1. Replace flip assembly with known good
one.
2. Place call to portable phone and verify
ability to answer by opening flip.
3. If fault still present, replace original flip
assembly and proceed to c.
1. Replace the Keypad/Display board with a
known good one.
2. Place call to portable phone and verify that
the fault has been eliminated.
3. If original Keypad/Display board is at fault,
examine it for improper solder and/or
connections. Likely fail components: J500.
1. Replace the Logic/RF board with a known
good one.
2. Place call to phone and verify that the fault
has been eliminated.
3. If original Logic/RF Board Assembly is at
fault, examine it for improper solder and/or
connections.
1. Check connections, if OK unsolder the
supply wires to the motor and unclip the
motor from the board.
2. Replace the motor with a known good one.
Reassemble unit.
3. Place call to portable phone and verify
vibrator feature functions.
4. If still at fault, examine it for improper solder
and/or connections. Likely fail components:
J603, Q604, and Q605.
1. Replace Logic/RF Board Assembly.
2. Place call to portable phone and verify that
the fault has been eliminated.
3. If Logic/RF Board Assembly is at fault,
examine it for improper solder and/or
connections.
12/9/97