TM 5-3805-291-23-1
TROUBLESHOOTING WITHOUT A DIAGNOSTIC CODE - CONTINUED
0008 00
Table 2. Electrical System Troubleshooting - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Backup Alarm Always Off - 3. Check backup alarm circuit for an open 1. If wiring harness is OK, go to Test 4.
4.
circuit.
2. If there is an open circuit in wiring
Continued.
(a) Turn engine start switch and
harness, open circuit is in wire 321 BR
battery disconnect switch to OFF
(backup alarm signal) or wire P990 BR
position (TM 5-3805-291-10).
(return signal). Replace wiring harness
(b) Disconnect J1 and J2 wiring
in question (WP 0195 00 thru WP 0201
harness connectors from
00).
powertrain ECM (WP 0063 00).
(c) At wiring harness connector for
backup alarm, place a jumper from
contact 1 to contact 2.
(d) Bypass switch side of backup
alarm relay with jumper wire.
(e) At wiring harness connector J2,
measure resistance from J1-12
(backup alarm signal) to J2-8
(return signal).
4. Check if problem is still active.
1. If problem has been corrected, initial
(a) Inspect and clean harness
problem was probably caused by a poor
connector contacts.
electrical connection and/or a short in
(b) Remove jumper from relay and
a harness connector that was
reconnect all harness connectors.
disconnected and reconnected.
(c) Start engine (TM 5-3805-291-10).
Resume normal machine operation.
2. If problem still exists, replace backup
alarm relay (WP 0053 00).
3. If problem still exists, replace
powertrain ECM (WP 0063 00).
1. Check backup alarm circuit for a short
1. If wiring harness is OK, go to Test 2.
5.
Backup Alarm Always On.
to +battery circuit.
2. If there is a short in wiring harness,
(a) Turn engine start switch and
short is between wire 321 BR (backup
battery disconnect switch to OFF
alarm signal) and circuit with low
position (TM 5-3805-291-10).
resistance measurement. Replace
(b) Disconnect wiring harness from
wiring harness in question (WP 0195
backup alarm (WP 0094 00).
00 thru WP 0201 00).
(c) Disconnect wiring harness
connector J1 and connector J2
from powertrain ECM (WP 0063
00).
(d) At wiring harness connector J2,
measure resistance from J1-12
(backup alarm signal) to all
possible sources of + battery.
Check resistance to all connectors
used in ECM harness connector.
