Ford 2003 Mustang Workshop Manual page 2351

PINPOINT TEST B: TRANSMISSION FLUID TEMPERATURE (TFT)
SENSOR
NOTE: Refer to the Transmission Connector Layouts preceding these pinpoint tests.
B1 ELECTRONIC DIAGNOSTICS
Check to make sure the transmission harness
connector is fully seated, pins are fully engaged in
connector and in good condition before proceeding.
Connect the diagnostic tool.
Key in ON position.
Select Diagnostic Data Link.
Select PCM.
Select PID/Data Monitor and Record.
Enter the following diagnostic mode on the diagnostic
tool: PIDs; TFT, TFTV.
Does the vehicle enter PID/Data Monitor and
Record?
B2 WARM-UP/COOL-DOWN CYCLE
While monitoring the TFT PIDs, carry out the
following test: If transmission is cold, run transmission
to warm it up. If transmission is warm, allow
transmission to cool down.
Do the TFT PIDs increase as the transmission is
warmed up or decrease as the transmission is
cooled or does the TFT or TFTV drop in and out
of range?
B3 ELECTRICAL SIGNAL CHECK
Key in ON position.
Remove transmission fluid pan.
Visually inspect the lead frame and connectors for
damage.
Measure the voltage with the positive lead to positive
TFT at sensor pin and negative lead to a good
ground.
Test Step Result / Action to Take
Yes
GO to B2 .
No
REPEAT procedure to enter PID. If
vehicle did not enter PID, REFER
to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual for diagnosis of
PCM.
Yes
If the TFT PIDs increase as the
transmission is warmed or
decrease as the transmission is
cooled, CLEAR all DTCs. ROAD
TEST to verify if concern is still
present. If concern is still present,
REFER to Diagnosis By Symptom
in this section to diagnose
transmission overheating.
If the TFT or TFTV drop in and out
of range, INSPECT for intermittent
concern in the internal/external
harness, sensor or connector.
No
GO to B3 .
Yes
GO to B4 .
No
CHECK for open or short circuit in
vehicle harness, internal harness
or a PCM concern.