Motorola APX 7500 Detailed Service Manual page 148

7-32
~690mVrms tone not present
Is there a 1kHz tone
No
greater than 600mVrms
at T1800-6?
Yes
Is there continuity
No
between K1802-3 &
K1802-4?
Yes
Verify C1826, R1818,
K1802 & R2839 are
placed properly & resistor
values are correct.
September 9, 2011
Troubleshooting Charts and Error Codes Troubleshooting Charts
Is there a 1kHz tone
No
greater than 600mVrms at
T1800-1?
Yes
No
Is T1800 placed
properly?
Yes
Replace T1800.
Verify K1802, R2839,
Q1812, C1870, R1831 &
R1857 are placed properly
& resistor values are
correct.
No
Does Q1812-3
measure ~1.1Vdc?
Yes
No
Does K1802-1
measure ~2.3Vdc?
Yes
Replace K1802.
Do high speed board conn.
pins J21-4 & J21-5 have continuity
w/ Mainboard's C1860 &
T1800-3 respectively?
Yes
Verify C1860 & C1861
are placed properly.
Place T1800 in its correct
orientation and verify all
pins are making proper
contact with their solder
pads.
Does Q1812-2
measure ~2.8Vdc?
Yes
Replace Q1812.
There may be an issue with
the internal board routing of
VCC_5V.
Figure 7-30. 4-Wire Wireline TX Audio - C
Verify LINE2+ (J21-4) & LINE2-
(J21-5) are being routed
No
properly through the high speed
board & flex cable to C1860 &
T1800-3 respectively.
No
Reprogram/Replace
Consolette Mainboard.
68009482001