TM 5-3805-290-23-1
ELECTRICAL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0013 00
5V ENGINE PRESSURE SENSOR SUPPLY CIRCUIT TEST - CONTINUED
N OT E
When sensors are disconnected and engine start switch is in ON position, open circuit diagnostic codes will
be active or logged when +5V diagnostic codes are no longer active. This is normal. Clear these diagnostic
codes after this test step is completed.
f.
Expected Results. Original +5V diagnostic code remains active.
(1)
If +5V diagnostic code is still active, harness is cause of problem. Leave sensors disconnected. Proceed to
step 5.
(2)
If +5V diagnostic code is not active when a specific sensor is disconnected, connect sensor that is sus-
pected of causing problem. If problem returns after connection of sensor, disconnect sensor. If problem
disappears after disconnection of sensor, replace sensor. Clear all diagnostic codes. Verify repair elimi-
nates problem.
5.
Check engine harness.
a.
Turn engine start switch to OFF position (TM 5-3805-290-10).
b.
Disconnect ECM connector. Verify these +5V engine pressure sensors attached to ECM connectors are discon-
nected.
(1)
Engine oil pressure sensor (WP 0066
00).
(2)
Boost pressure sensor (WP 0065 00).
c.
Measure resistance from P1:26 +5V Engine Oil
Pressure Sensor to each of these terminals:
(1)
P1:14 Boost Pressure
(2)
P1:24 Engine Oil Pressure
d.
Wiggle harness during measurement to reveal
any intermittent short condition.
427-B0668
e.
Expected Results. Each resistance measurement is more than 20 Ohms.
(1)
If +5V line is not shorted in engine harness, ensure engine harness is connected to ECM (WP 0053 00) and
all sensors are connected (WP 0065 00 and WP 0066 00). There does not appear to be a problem at this
time. Clear all diagnostic codes. Continue to troubleshoot until original condition is resolved.
(2)
If +5V line is shorted in engine harness, replace engine wiring harness (WP 0170 00). Clear all logged
diagnostic codes. Verify repair eliminates problem.
0013 00-9
