Ford 2003 Mustang Workshop Manual page 3535

F1 CHECK CIRCUIT 70 (LB/WH) FOR OPEN
Key in OFF position.
Inspect the DLC C251 Pin 7, Circuit 70 (LB/WH) for
damage, repair as necessary.
Disconnect: GEM C201e.
Measure the resistance between GEM C201e Pin 6,
Circuit 70 (LB/WH), harness side and DLC C251 Pin 7,
Circuit 70 (LB/WH), harness side.
Is the resistance less than 5 ohms?
F2 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — GEM C201e DISCONNECTED
Key in ON position.
Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side.
Is the voltage indicated in either measurement zero
volts?
F3 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — IN-LINE C314 DISCONNECTED
Key in OFF position.
Disconnect: In-Line C314.
Key in ON position.
Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side.
Test Step Result / Action to Take
Yes
GO to F2 .
No
REPAIR Circuit 70 (LB/WH)
between the GEM C201e and
DLC C251. TEST the system
for normal operation.
Yes
CONNECT the GEM module
C201e. GO to F3 .
No
INSTALL a new GEM. For
additional information, REFER
to Section 419-10 . TEST the
system for normal operation.
Yes
GO to F4 .
No
GO to F5 .