5c-5
Service Error Messages
601   −12 V power supply failure
Description   The −12 V diagnostic test point decreased by more than approximately 
0.4 V.
Cause   Either the −12 V regulator on the A3 motherboard has failed, or the −15 V 
supply on the A2 power supply assembly has failed.
What To Do   Check the output of both the −15 V and −12 V supplies.
603   +12 V power supply failure
Description   The +12 V diagnostic test point decreased by more than approximately 
0.4 V.
Cause   Either the +12 V regulator on the A3 motherboard has failed, or the +15 V 
supply on the A2 power supply assembly has failed.
What To Do   Check the output of both the +15 V and +12 V supplies.
604   +38 V power supply failure
Description   The +38 V diagnostic test point decreased by more than approximately 
2.2 V.
Cause   The +38 V supply on the A2 power supply has failed.
What To Do   Check the +38 V supply.
605   ALC out-of-lock div het main band
Description   The ALC loop is out of lock in the indicated bands.
Cause   Either the A6 output has failed, or the signal from the A5 synthesizer has 
failed or the A4 reference has failed. If only the het band has failed it is 
possible that the A4 reference has failed.
What To Do   Check the input to the A6 output from the A5 synthesizer and the A4 
reference.
608   Synth out-of-lock div het main band
Description   The synthesis loop is out of lock in the indicated bands.
Cause   Either the A5 synthesizer has failed, or the signal from the A4 reference 
has failed.
What To Do   Check the input to the A5 synthesizer from the A4 reference.