Ford 2003 Mustang Workshop Manual page 3255

illumination position.
Measure the voltage between the instrument cluster C220b
pin 4, circuit 19 (LB/RD), harness side and ground.
Is the voltage greater than 10 volts?
B2 CHECK GROUND TO INSTRUMENT CLUSTER
Place the headlamp switch in the OFF position.
Measure the resistance between the instrument cluster
C220b pin 1, circuit 1205 (BK), harness side and ground.
Are the resistances less than 5 ohms?
PINPOINT TEST C: THE CLIMATE CONTROL ILLUMINATION IS
INOPERATIVE
C1 CHECK VOLTAGE TO CLIMATE CONTROL ILLUMINATION
Disconnect: Function Selector Switch C294b .
Place the headlamp switch in the ON position.
Rotate the instrument panel dimmer switch to the full
illumination position.
Measure the voltage between the function selector switch
C294b pin 2, circuit 19 (LB/RD), harness side and ground.
Is the voltage greater than 10 volts?
C2 CHECK GROUND TO CLIMATE CONTROL
Test Step
No
REPAIR the circuit. TEST
the system for normal
operation.
Yes
INSTALL a new instrument
cluster. REFER to Section
413-01 . TEST the system
for normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation.
Result / Action to Take
Yes
GO to C2 .
No
REPAIR the circuit.
TEST the system for
normal operation.