BenQ March Service Manual page 84

BenQ
b) U1 is at fault
c) Other
components are at
fault.
5.Buzzer no a) Components shift 4. Disassembly to visually inspect the
function
b) U1 is at fault
c) Other
components are at
fault.
6.Vibrator no a) Components shift 4. Disassembly to visually inspect the M1.
function
3. Measure the waveform of the U7.2. If
the U7.2 doesn' t output any signal when
LED function is executed, U1 is at fault.
4. If it is not at fault, proceed to c.
3. Measure the waveform of the U7.6,
BQ2.2, and BQ2.3 when LED function
is executed.
4. If any pin is no signal, replace the
component relative to that pin.
U13. If the spring of the U13 becomes
deformed, replace the U13.
5. Visually inspect the R48, BQ3, R45,
and R71. If any component is shifted,
replace the components.
6. If they are not shifted, proceed to b
3. Measure the waveform of the D16.1. If
the D16.1 doesn' t output any signal
when Buzzer function is executed, U1 is
at fault.
4. If it is not at fault, proceed to c.
3. Measure the waveform of the BQ3.3,
BQ3.2, and BQ3.1 when Buzzer
function is executed.
4. If any pin is no signal, replace the
component relative to that pin.
If the spring of the M1 becomes
deformed and doesn' t contact well with
PCB pads, replace the M1.
5. Visually inspect the R46, BQ4, and
R49. If any component is shifted,
replace the components.
6. If they are not shifted, proceed to b
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Rev 1.0