Control Unit Assembly Removal; Typical Control Unit - Komatsu 930E-2 Shop Manual

CONTROL UNIT ASSEMBLY REMOVAL

(These instructions may be used with control unit
assemblies having SAE or Metri-Pak connector.)
Refer to Figures 13-14 and -15 for the following steps:
1. Remove the top cover of the control unit assembly
(Five screws).
Before removing the old control unit assembly,
observe wire position by wire function, not wire
color. Wire connections on some units are not
color coded.
2. Remove bolt and lock washer attaching "B+" buss
from the rectifier assembly to "B+" output termi-
nal.
3. Remove four attaching screws from the front of
the control unit assembly.
Pull control unit – face plate forward to permit
easy disconnection of wire ends from "R" (or
phase terminals) and "B+" terminals. Leave the
regulator harness with grommet resting on frame
while sliding face plate up and off grommet.
4. Remove the phase lead wire from "R" terminal (or
phase terminals) on the face plate. Be careful not
to move or reroute the phase lead.
5. Disconnect the field leads from "F-" terminal and
"B+" terminal of the terminal block.
6. Disconnect the regulator harness ground wire
from the end housing. (lead #2)
7. Remove the terminal block from the housing.
NOTE: Two nuts are used as spacers underneath the
terminal block on attaching screws.
8. Desolder "B+" lead from the terminal block. Take
care to position "B+" lead coming from the recti-
fier assembly.
Do not cut "B+" lead at terminal block.
"B+" lead does not have slack.
9. Discard the old face plate assembly with regulator
connector harness assembly.
10. Clean old RTV from the top and the face of control
unit area of the housing.
M13003 04/01
1. Ignition (E)
(Harness Lead #4)
2. Relay (R)
3. Terminal Block
4. F- (Harness Lead #1)
1. Cover Screws (TOP)
11. Inspect leads from field coil and rectifier assembly
Niehoff Alternator Overhaul Manual
FIGURE 13-14. TYPICAL CONTROL UNIT
5. F+ (Harness Lead #3)
6. Ground Wire from Reg.
(Harness Lead #2)
7. B+ Buss Leads to
Rectifier
FIGURE 13-15.
2. Control Unit Screw
for chaffing, and repair as necessary.
M13-15