Is the voltage greater than 10 volts?
M2 CHECK THE GROUND TO THE BLEND DOOR ACTUATOR
Ignition OFF.
Measure the resistance between the blend door actuator C289 pin 8, circuit 57 (BK) and ground.
Is the resistance less than 5 ohms?
Yes
GO to
M3
.
No
REPAIR circuit 57 (BK). TEST the system
for normal operation.
M3 CHECK THE TEMPERATURE CONTROL POTENTIOMETER TOTAL RESISTANCE
Measure the resistance between temperature blend door actuator C289 pin 6, circuit 436 (RD/LG) and pin 4, circuit 438
(RD/WH).
Is the resistance between 4,500 and 5,500 ohms?
Yes
GO to
M6
.
No
If the resistance is less than 4,500 ohms,
GO to
M4
. If the resistance is greater
than 5,500 ohms, GO to
M5
.
M4 CHECK CIRCUITS 436 (RD/LG) AND 438 (RD/WH) FOR A SHORT TOGETHER
Disconnect: Temperature Control Potentiometer C294c.
Measure the resistance between temperature blend door actuator C289 pin 6, circuit 436 (RD/LG) and pin 4, circuit 438
(RD/WH).
Is the resistance less than 5 ohms?
Yes
REPAIR circuits 436 (RD/LG) and 438
(RD/WH) for a short together. TEST the
system for normal operation.
No
INSTALL a new temperature control
potentiometer. REFER to
Section 412-04
.
TEST the system for normal operation.
M5 CHECK CIRCUITS 436 (RD/LG) AND 438 (RD/WH) FOR AN OPEN
Disconnect: Temperature Control Potentiometer C294c.
Measure the resistance between temperature blend door actuator C289 pin 6, circuit 436 (RD/LG) and temperature control
potentiometer C294c pin 1, circuit 436 (RD/LG), and between temperature blend door actuator C289 pin 4, circuit 438 (RD/WH)
and temperature control potentiometer C294c pin 3, circuit 438 (RD/WH).
Are the resistances less than 5 ohms?
Yes
INSTALL a new temperature control
potentiometer. REFER to
Section 412-04
.
TEST the system for normal operation.
No
REPAIR the affected circuit. TEST the
system for normal operation.
M6 CHECK THE TEMPERATURE CONTROL POTENTIOMETER OPERATION
Page 34 of 47
2003 Taurus/Sable Workshop Manual
11/22/2011
http://www.fordtechservice.dealerconnection.com/pubs/content/~WS3H/~MUS~LEN/19/...
