MPI 40 Series - Head will Not Load; Bad Index Output; Bad Write Protect Output; Activity Indicator Does Not Light

5.6 HEAD WILL NOT LOAD
A. Check J5-2 for a low level. If output is low, replace the
head load solenoid (refer to paragraph 4.5.5).
B. Double-check the drive configuration for proper programming (refer
to section 6).
5.7 BAD INDEX OUTPUT
A. Block both index sensors' LED light path. If J7-8 or 10 are at a
low level, replace the index sensor assembly (refer to paragraph
4.5.15).
B. Remove diskette and close door. Check J7-8 and 10 for a low
level; if low check for correct signal levels throughout the index
logic. If either signal is high, replace the index sensor as-
sembly (refer to paragraph 4.5.15).
5.8 BAD WRITE PROTECT OUTPUT
A. Block both write protect sensors' LED light path. J6-9 and J5-8
should both be a logic high. If J6-9 is a low level, replace the
write protect sensor on the right as viewed from the front of the
drive (refer to figure 4-1). If JS-8 is a low level, replace the
write protect sensor on the left.
B. Unblock both write protect sensors' LED light path. J6-9 and JS-8
should both be a logic low. If J6-9 is a high level, replace the
write protect sensor on the right as viewed from the front of the
drive (refer to figure 4-1). If J5-8 is a high level, replace the
write protect sensor on the left.
c. Check for correct signal levels throughout the write protect
logic.
5.9 ACTIVITY INDICATOR DOES NOT LIGHT
A. Activate the activity indicator and look for a logic low signal on
J7-2.
B. If J7-2 is high, check activity indicator logic for correct signal
levels.
c. If J7-2 is low, look for a broken wire then replace the activity
indicator.
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