Ford 2003 Mustang Workshop Manual page 3297

side and ground.
Key in ON position.
Does the ABS indicator illuminate?
R3 CHECK CIRCUIT 603 (DG) FOR AN OPEN
Key in OFF position.
Disconnect: Instrument Cluster C220b.
Measure the resistance between the instrument cluster
C220b pin 15, circuit 603 (DG), harness side and the anti-
lock brake control module C135 pin 16, circuit 603 (DG),
harness side.
Is the resistance less than 5 ohms?
R4 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION
Disconnect all instrument cluster connectors.
Check for:
corrosion
pushed-out pins
Connect all instrument cluster connectors and make sure
they seat correctly.
Operate the system and verify the concern is still present.
Is the concern still present?
PINPOINT TEST S: THE SERVICE ENGINE SOON INDICATOR IS
NEVER/ALWAYS ON
Test Step
S1 CARRY OUT THE INSTRUMENT
No
GO to R3 .
Yes
GO to R4 .
No
REPAIR the circuit. TEST
the system for normal
operation.
Yes
INSTALL a new instrument
cluster. REFER to
Instrument Cluster
section. TEST the system
for normal operation.
No
The system is operating
correctly at this time.
Concern may have been
caused by a loose or
corroded connector.
CLEAR the DTCs.
REPEAT the self-test.
Result / Action to Take
in this