TM 5-3805-290-23-1
ELECTRICAL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0013 00
ENGINE PRESSURE SENSOR OPEN OR SHORT CIRCUIT TEST - CONTINUED
7.
Determine if short circuit is in connector or sensor.
a.
Thoroughly inspect connector for moisture.
b.
Inspect seals and reconnect sensor.
c.
Refer to Electrical Connectors Inspection (WP 0022 00).
d.
If short circuit diagnostic code reappears, sensor or pigtail harness connector is problem. Replace sensor (WP 0065
00 or WP 0066 00).
e.
Use MSD to verify there is short circuit diagnostic code. New sensor should be connected to harness at this time.
f.
Expected Results. Short circuit diagnostic code is not present when new sensor is connected.
(1)
If results are OK, replace sensor (WP 0065 00 or WP 0066 00) verify repair eliminates problem. Use MSD
to clear logged diagnostic codes.
(2)
If results are NOT OK, replace engine harness connector (WP 0170 00).
8.
Create short circuit between signal and common terminals at engine harness connector.
a.
Turn engine start switch to ON position (TM 5-3805-290-10).
b.
Use jumper wire 6 in. (15 cm) long.
N OT E
Monitor Active Diagnostic Code screen of MSD before and after installing jumper wire.
c.
Install jumper on engine harness connector. Install one end of jumper at sensor signal (terminal C). Install other
end of jumper at common connection for pressure sensor (terminal B). Wait at least 15 seconds for activation of
short circuit diagnostic code.
d.
Expected Results. Short circuit diagnostic code is active when jumper is installed. Open circuit diagnostic code is
active when jumper is removed.
(1)
If results are OK, engine harness and ECM are OK. Replace suspect sensor (WP 0065 00 or WP 0066 00).
Use MSD to verify repair eliminates problem.
(2)
If results are NOT OK, open circuit diagnostic code remains active when jumper is installed. Most proba-
ble location for open is in sensor common or sensor signal wire in engine harness between ECM and sen-
sor. Remove jumper. Proceed to step 9.
9.
Check operation of ECM by creating open and short circuits at ECM connector.
a.
Turn engine start switch to OFF position (TM 5-3805-290-10).
b.
Disconnect J1/P1 ECM connector (WP 0053 00). Thoroughly inspect both halves of connectors for signs of corro-
sion or moisture.
c.
Refer to Electrical Connectors Inspection (WP 0022 00).
d.
Reconnect J1/P1 ECM connector.
e.
Turn engine start switch to ON position (TM 5-3805-290-10). Monitor Active Diagnostic Code screen of MSD.
Wait at least 15 seconds for activation of code.
f.
Open circuit diagnostic code should be active for suspect sensor.
0013 00-37
