Motorola ASTRO XTSTM 4000 Detailed Service Manual page 71

Troubleshooting Charts: DC Supply Failure
DC Supply Failure–Page 4
4
Check voltage at
C14
Voltage =
5.0 Vdc +/ -
5%?
Yes
Check voltage at
C27
Voltage =
3.0 Vdc +/ -
5%?
Yes
Check voltage at
C17
Voltage =
3.0 Vdc +/-
5%?
Yes
END
6871620L01-C
Check Q4, E5, D1,
No
C10, C11, C12,
C14, Q1301 &
R1709
No
Check L10, D3,
C25, C26, C27,
C28 & C30
No
Check D2, C15,
C16, C17 & C9
No
Component
OK?
Yes
Replace U1
No
Component
OK?
Yes
Replace U3
No
Component
OK?
Yes
Replace U2
5-9
Replace problem
components
Replace problem
components
Replace problem
components
May 28, 2008