STEP/SEQUENCE
RESULT
WHAT TO DO NEXT
TM 9-2320-363-20-1
Section 4
TROUBLESHOOTING CHARTS
E. FLASH CODE: 17
J1587 CODE: P72 3 - BYPASS POSITION CIRCUIT FAILED HIGH (HIGH VOLTAGE)
NOTE - This chart is only to be used if:
1) All basic mechanical checks and physical inspections have been performed with no problem found, and
2) Diagnosis of DDEC-III was started at step Start-1, pg 3-345.41 and you have now been referred here.
17-1 Multiple Code Check
Were there any other active
No other codes.
Go to 17-2.
codes besides 72/3?
Yes, any or all
Go to ENG5V-1 pg 3-345.413.
of the following codes:
110/3 or 4, 175/3 or 4,
174/3 or 4, 102/3 or 4,
100/3 or 4, 94/3 or 4,
101/3 or 4, 73/3 or 4,
Yes - But none
Go to 17-2.
of the above.
17-2 Sensor Check
Turn ignition off.
Code 72/4 (and any
Go to 17-3.
Disconnect the BPS
codes except 72/3).
connector.
Start and Run Engine at idle
Code 72/3 (and any
Go to 17-5.
Read Active codes.
other codes.
17-3 Return Circuit Check
Turn ignition off.
Less than or
Go to 17-4.
Install a jumper wire
equal to 5 ohms.
between pins A and B of BPS
connector.
Greater than 5 ohms.
Return Line (ckt#452) is open.
Disconnect engine harness
or open.
Repair open. Then go to 17-
connector at the ECM.
30.
Read Resistance between
cavities R1 (902) and Y2(452)
on the engine harness connector.
17-4 Check BPS Connectors
Inspect terminals at BPS
Terminals and connectors
Replace BPS. Then go to
connectors (sensor side and
are okay.
17-30.
harness side) for damaged; bent,
corroded, and unseated pins
Problem found.
Repair terminals/connectors.
or sockets.
Then go to 17-30.
Change 3 3-345.217
