Off - Ford 2003 Mustang Workshop Manual

Monitor the GEM PID DECKLID, while opening and closing
the luggage compartment lid.
Does the GEM PID DECKLID agree with the dome switch
position?
B5 CHECK THE COURTESY LAMP CIRCUITS
Close the luggage compartment lid and all doors are closed.
Turn the dome and map lamp switches to the off position.
Are the courtesy lamps illuminated?
B6 CHECK THE GEM CONTROL OF THE COURTESY LAMPS
Trigger the GEM active command COURTESYL ON and then

OFF.

Do the courtesy lamps illuminate when the GEM active
command COURTESYL ON is triggered, and go out when
the GEM active command COURTESYL OFF is triggered?
B7 CHECK THE GEM FOR AN INTERNAL FAULT
Trigger the GEM active command COURTESYL ON, then
OFF.
Can an audible click be heard coming from the GEM,
while triggering the active command COURTESYL ON?
B8 CHECK CIRCUIT 1034 (BK/WH) FOR VOLTAGE
Disconnect the dome lamp C929 (coupe) or map lamp C978
(convertible)
Trigger the GEM active command COURTESYL ON.
Measure the voltage between dome/map lamp C929 (coupe)
Pin 3 or map lamp C978 (convertible) Pin 4, Circuit 1034
(BK/WH), harness side and ground.
Is the voltage greater than 10 volts?
B9 CHECK CIRCUIT 1006 (DG/WH) FOR OPEN
NOTE: Verify battery voltage at CJB Fuse 7 (20A) before
carrying out this test.
Disconnect: GEM C201a.
Measure the voltage between GEM C201a Pin 1, Circuit 1006
(DG/WH), harness side and ground.
Yes
GO to B5 .
No
GO to B16 .
Yes
GO to B12 .
No
GO to B6 .
Yes
INSTALL a new GEM. For
additional information,
REFER to Section 419-
10 . REPEAT the self-test.
CLEAR the DTCs.
No
GO to B7 .
Yes
GO to B8 .
No
INSTALL a new GEM. For
additional information,
REFER to Section 419-
10 . REPEAT the self-test.
CLEAR the DTCs.
Yes
GO to B11 .
No
GO to B9 .
Yes
GO to B10 .
No
REPAIR the circuit.
REPEAT the self-test.
CLEAR the DTCs.