Technical data

Chapter 8: Troubleshooting
Series SPB Audio Boosters Manual, Revision A
8-5
8.2.1 Procedure A
If the green AC LED is “OFF” and all other LEDs are “OFF,” a power loss condition has
occurred. A power loss condition may be caused by:
Loss of AC input voltage and battery back-up voltage.
Faulty internal wiring between the power supply module (SPBPS) and the ± DC IN (TB4) on the
mother board and batteries missing.
Faulty mother board.
Faulty Power Supply Module (SPBPS).
Perform the following:
1. Check for 24 VDC at TB2 on the mother board. Check for battery installation.
2. Check AC fuse F1.
3. If the 27VDC is present on TB2, replace the mother board.
NOTE: Mark all wires before removing components. When the trouble is repaired and before
testing, replace all wires to the proper locations and replace all covers.
8.2.2 Procedure B
If the green AC LED is “ON,” the yellow TROUBLE LED is “ON,” and D49, BAT TRB LED is
“ON,” Battery Voltage is below 20.4 VDC or battery is missing. A battery trouble condition
might be caused by:
1. Batteries are missing.
2. Battery wiring is incorrect.
3. Batteries are defective.
4. Battery charging section of mother board is inoperable.
Perform the following:
1. Check battery compartment for the presence of batteries. If batteries are not installed,
install them.
2. Ensure that the batteries are properly wired.
3. If Steps 1 and 2 are satisfied, replace the batteries.
4. Check for 24VDC at ± BATTERY connection at TB2 on the mother board. If the
voltage is below 20.4 VDC, battery-charging section of the motherboard is
inoperable. Replace the motherboard (SPB-160 / SPB-80/4).