Ford 2003 Mustang Workshop Manual page 3299

Does the voltage alternate between 0 volts and 10 volts with
the turn signal on?
T3 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 U: THE TRACTION CONTROL INDICATOR IS
NEVER/ALWAYS ON
Test Step
U1 DETERMINE IF THE TRACTION
CONTROL INDICATOR IS ALWAYS ON
Observe the traction control indicator.
Is the indicator always on?
Result / Action to Take
Yes
REFER to Section 206-09B
No
Yes
INSTALL a new
instrument cluster.
REFER to
Instrument Cluster
in this 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.
.