TM 5-2410-241-23-1
0019
Table 2. Engine Troubleshooting Procedures - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
274-4 Atmospheric Pres-
1. Connect MSD (WP 0016). Select
1. If active 274-4 code is present,
sure Short to Ground
3176C D7 engine ECM and check
proceed to step 2.
for Diagnostic Codes or Event
2. If no active codes are present,
Codes (WP 0013).
problem does not exist at this
time. Resume normal operation.
2. Turn ignition switch and battery
disconnect switch to OFF position
(TM 5-2410-241-10).
3. Disconnect atmospheric pressure
sensor connector N-C4 (WP
0018, Figure 35) from Atmo-
spheric pressure sensor.
4. Turn battery disconnect switch
and ignition switch to ON position
(TM 5-2410-241-10).
5. Check for Diagnostic Codes or
1. If active 274-3 code is present,
Event Codes (WP 0013).
replace atmospheric pressure
sensor (WP 0090). Ensure all har-
ness connectors are reconnected.
Verify correct operation of
machine (TM 5-2410-241-10).
2. If active 274-4 code is present,
proceed to step 6.
6. Turn ignition switch and battery
disconnect switch to OFF position
(TM 5-2410-241-10).
7. Disconnect engine ECM connec-
tor N-C1 (WP 0018, Figure 2)
from ECM.
8. Using digital multimeter
1. If continuity is found, proceed to
(WP 0296), test for continuity
step 9.
between pin B on atmospheric
2. If continuity is not found, replace
pressure sensor connector N-C4
ECM harness (WP 0105). Ensure
(WP 0018, Figure 35) and pin 3
all harness connectors are recon-
on engine ECM connector N-C1
nected. Verify correct operation of
(WP 0018, Figure 2).
machine (TM 5-2410-241-10).
9. Using digital multimeter
1. If continuity is found, proceed to
(WP 0296), test for continuity
step 10.
between pin C on atmospheric
2. If continuity is not found, replace
pressure sensor connector N-C4
ECM harness (WP 0105). Ensure
(WP 0018, Figure 35) and pin 14
all harness connectors are recon-
on engine ECM connector N-C1
nected. Verify correct operation of
(WP 0018, Figure 2).
machine (TM 5-2410-241-10).