Agilent Technologies 4395A, Service Manual

Page: 225 / 343

Figure 8-5. A1 Eight LEDs' P attern
2. Check Error Messages
T urn the analyzer p o w er on. Chec k no error message app ears on the LCD.
If no error message is display ed, con tinue with the Che ck A1 DRAM and Flash Memory in
this ST AR T HERE.
If one of error messages listed b elow is display ed, follo w the instruction describ ed b elow. F or
the other message, see the Err or Messages in Messages.
Error Messages Instruction
POWER ON TEST FAILED This indicates the p o w er on selftest failed. Con tinue with
the next Che ck Power On Selftest in the c hapter 6.
EEPROM CHECK SUM ERROR This indicates that the correction constan ts stored in the
EEPR OM on the A1 CPU are in v alid or the EEPR OM is
faulty . Rewrite all correction constan ts in to the EEPR OM.
F or the detailed pro cedure, See the A djustments c hapter in
this man ual. If the rewriting is not successfully p erformed,
replace the EEPR OM and then rewrite the all correction
constan ts in to the new EEPR OM.
Svc (Status Annotation) This indicates that the correction constan ts stored in the
EEPR OM on the A1 CPU are in v alid or the EEPR OM is
faulty . See the instruction of the EEPROM CHECK SUM ERROR
message.
POWER FAILED ON - - - One or some of A2 p o w er supplies, +15 V, +8.5 V, +5.3 V,
+5 V, -5 V, -15 V are display ed in - - - of the message.
The display ed p o w er supplies are sh ut do wn due to the
trouble on the A2 p ost-regulator. Con tinue with the Power
Supply T r oublesho oting c hapter.
Digital Control Troubleshooting 8-7