Motorola Moto X Force Troubleshooting Manual page 39

Debug Procedure: Headset
• Check the pins on the headset jack for any bent pins or missing pins (In
rear housing)
• On the TOP FLEX:
– ESD Diodes VR4900, VR4901, VR4902, VR4903, VR4904 must be
open circuit. Measure these with a DMM to ground. If any short circuit
is found, replace the ESD diode.
– Shunt caps C4900, C4901, C4902, C4903, and C4904 must not be
shorted across.
– Check that there are slight indentations on the headset pads,
preferably centered. If any indentations fall close to the gold pad edge,
there may be an alignment issue.
• On the MAIN PCB:
– U4800 must have voltage on the VDD line, and can be probed on
C4813 or C4819. This should measure 1.8V nominally.
– Check that the J800 B2B connector is seated properly and there is no
damage to either the connector (TOP FLEX-side) or receptacle (MAIN
PCB-side).
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Moto X Force/DROID Turbo 2
BASEBAND TROUBLESHOOTING GUIDES