A2/A3 Assembly Failure; Replacement Procedures - HP 3457A Service Manual

Service
8-46.
A2/A3 Assembly Failure Indications 8-47. Failures in the floating common section of the instrument
(A2/A3 assemblies) can be detected by running the TEST routine. A failure detected by the test routine will
be indicated by a display of TEST FAILED and the error annunciator flashing. Not all errors require
replacement of the A2/A3 assemblies t o correct the problem. The test routine detects calibration errors as
well as hardware errors.
8-48. T o determine what failure occurred during the test, read the
ERROR register
(Press the ~ l u e S H I F T key
then the ERROR key).
The error message should read
HARDWARE ERROR.
Other messages d o not indicate a
circuit failure. If the error annunciator is still flashing, read the other messages t o clear the register. Read
the AUXERR? register.
(Preps the Blue S H I F T key then the NPLC
/
A co~ifigurution key. Use the
scroll key to dis-
play the A UXERR? comnlund urid press the ENT key).
The display will show AUXERR?: and an error code num-
ber. The following is a complete list of the AUXERR? codes:
ERROR
CODE
D E S C R I P T I O N
Isolation error durlng operatlon in any mode (self-test, auto-cal, measurements, etc.)
Slave processor self test failure
Isolation self-test failure
Integrator convergence error
Front end zero measurement error
Current source, gain selection, Input dlvlder error
Amps self-test fallure
AC ampllfler DC offset test fallure
AC flatness test error
Ohms precharge fallure durlng auto-cat
32k ROM checksum failure
8k ROM checksum fallure
Non-volatlle RAM fallure
Volatlle RAM failure
Callbratlon RAM protection fallure
The error codes which apply t o the TEST routine are numbered I6 through 512. If more than one test fails
the error codes will be summed together. As an example: If the front end zero measurement test and the
AC flatness test failed, the error code displayed would be 272 (256
+
16).
8-49. Front end zero measurement errors (error code 16) and AC flatness test errors (error code 256) can of-
ten be remedied by calibration. Refer t o Section V for the appropriate procedures. Error codes 8, 32, 64,
128, and 512 normally indicate a component failure.
8-50. Replacement Procedures
8-51.
Procedures for the removal and replacement of the
PC assemblies are contained in Section V1 of this
manual. Please observe clean handling techniques and anti-static procedures when handling the
PC
as-
semblies.