Motorola 880, Service Manual

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52 68P09403A50 12/9/97
Dual Band 880/890 (DCS/GSM)
Logic/Processing Supplement 4 - Unit Powers Down When Twisted
This indicates possibilities of a dry/cold solder joint that normally makes contact.
However, when the PCB is twisted or flexed the contact is broken causing power
down. Inspect the following components for dry joints:
• J500 connector to Display board
• Battery contact assembly
• External device connector assembly (J400)
• Y702
• CR221
• All chips
If the above analysis does not identify the fault, return the PCB to a Motorola Hi Tech
Center.
Logic/Processing Supplement 5 - PCB Draws Current When Off
• Ensure that the +6.5V power supply is being applied to the PCB , and that the PCB
is switched off.
• Spray the top RF/Logic circuitry with freezer spray until the PCB is frosted white.
If the frost melts on a specific component(s) before the normal defrost process
occurs, replace the component(s).
• If the above process does not eliminate the fault, spray the bottom RF/Logic
circuitry with freezer spray until the PCB is frosted white. Once again, if the frost
melts on a specific component(s) before the normal defrost process occurs, replace
the component(s).
• If steps 2 and 3 fail to eliminate the fault, or the defective component(s) are not
covered by this level of repair, return the PCB to a Motorola Hi Tech Center.