TM 5-3805-290-23-1
ELECTRICAL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0013 00
ELECTRICAL POWER SUPPLY CIRCUIT TEST - CONTINUED
4.
Use bypass harness and adapter for MSD to bypass machine wiring.
13
WARN I N G
Batteries give off flammable fumes which can explode. To avoid injury or death, do not strike match, cause
spark, or smoke in vicinity of battery.
13
13
CAU T I ON
Do not connect bypass harness to battery until 20-Amp inline fuse has been removed from +battery line. If
fuse is not removed before connection to battery, spark may result.
N OT E
This bypass harness is only for test applications. This bypass harness may only be left only on engine tem-
porarily. The bypass harness can be used to determine if cause of intermittent problem is interruptions in
battery power to ECM or engine start switch circuit.
a.
b.
Disconnect harness connector J1/P1 from ECM (WP 0053 00).
c.
Connect bypass harness and adapter to ECM connector J1.
d.
Remove inline fuse from +battery wire of bypass harness. Connect unswitched +battery wire and -battery wire
directly to battery posts.
N OT E
This bypass directly connects circuit for engine start switch to ECM. The ECM will remain powered until
connection to unswitched +battery line is disconnected from battery post. Remove 20-Amp fuse from inline
fuse holder to power down ECM. Do not connect bypass to battery posts without first removing 20-Amp
inline fuse. Do not remove bypass from battery posts without first removing 20-Amp inline fuse.
e.
Connect MSD to bypass harness data link connector. Turn engine start switch to ON position (TM 5-3805-290-10)
and verify communication is established.
f.
Restore all wiring to original condition after testing.
427-B0683
0013 00-32