Specifications

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Troubleshooting
Troubleshooting Assembly–Level Problems
Self–Tests 11xx: A18 CPU Self–Test Errors
1100 Power Supply
The A18 CPU self–test verifies the presence of the supplies listed. These supplies are not checked
during the turn–on check and are not necessary for the turn–on check to pass.
1. After running self–test, View
Details and see which supply failed.
2. If the 10 VRef has failed, replace the A18 CPU. The 10 VRef is generated on the A18 CPU and
used for the ADC circuit.
3. For a self–test failure other than the 10 VRef, measure the appropriate connector pin listed in
the following table.
4. If the voltages are present on the A31 Motherboard, turn power off, remove the A18 CPU and
inspect the connector. If the pins look good, replace the A18 CPU.
Connector P223 Supply Voltage Voltage Range
Pin 1 –5.2 Vdc –5.2 ±.1 Vdc
Pin 17 –6 Vdc –6 ±.1 Vdc
Pin 18 +9 Vdc +9 ±.1 Vdc