GMC 1976 ZEO 6083 Maintenance Manual page 433

Figure 56-Ohmmeter Check of Ignition Coil
h. Check secondary of coil (step 2, figure 56).
Use high scale. Reading should not be infinite .
i. If reading is infinite, check cap and rotor
button for arced or burned condition. If necessary,
replace cap. If cap and carbon button do not appear
defective, replace ignition coil .
8. If red light on module tester J-24642 stays on,
either the module or the pickup coil is defective. To
determine which is defective, continue with Test No .
2 (figure 57).
a. With distributor cap removed and J-24642
module tester three-way connector and battery leads
connected as in Test No . 1 connect green and white
leads to module (figure 57).
NOTE :
Green and white leads will connect only
one way . Test connections now will test module
only .
b. Press and hold test button on J-24642
tester . If green light now comes on, the module is
BATTERY LEAD CONNECTOR
CONNECTED TO BATTERY TERMINALS
ENGINE ELECTRICAL
6Y- 5 3
Figure 57-Test No . 2 Using Tool J-24642
okay, so the pick-up coil is defective. If the red light
stays on, the module is defective.
NOTE:
If necessary to replace pick-up coil,
remove distributor from engine, drive pin from
gear, remove rotor and shaft assembly from
housing and remove thin "C" washer ; to replace
pick-up coil as described in this section under
distributor disassembly.
If necessary to replace module, remove connector,
white and green leads, to attaching screws and re-
place module . Special silicone grease as supplied
with new module must be applied to distributor and
module to dissipate heat.
c. Remove J-24642 test leads, replace parts as
required, if removed, replace distributor and cap as-
sembly .
9. Module may be tested on bench using Tester
J-24642 (figure 58).
Connect the two-way connector of the analyzer
to the module and the green and white analyzer leads
to the corresponding green and white terminals of
the module . Connect red elad of tester to 12 volt