Pinpoint Test E: The Blower Motor Does Not Operate - Ford F-150 1999 Workshop Manual

1999 F-150/250 Workshop Manual
D6 CHECK THE A/C CONTROL POTENTIOMETER
D7 CHECK CIRCUIT 57 (BK)

PINPOINT TEST E: THE BLOWER MOTOR DOES NOT OPERATE

CONDITIONS
E1 CHECK FUSE 24 (10A)
Fuse 24 (10A)
http://www.fordtechservice.dealerconnection.com/pubs/con...
Are the resistances less than 5 ohms?
Yes
GO to D6.
No
REPAIR the circuit(s) in question. TEST the system for normal operation.
Measure the resistance between the blend door actuator control terminal 2 Circuit 437 (Y/LG) and terminal 3
Circuit 436 (R/LG).
Is the blend door actuator control at full WARM greater than 3,000 ohms and at full COOL less than 300
ohms? Is there a linear variation in the resistance between COOL and WARM?
Yes
GO to D7.
No
REPLACE the blend door actuator control. TEST the system for normal operation.
Measure the resistance between the A/C electronic blend door actuator motor C229-8, Circuit 57 (BK), and
ground.
Is the resistance less than 5 ohms?
Yes
REPLACE the A/C electronic blend door actuator motor. TEST the system for normal operation.
No
REPAIR Circuit 57 (BK). TEST the system for normal operation.
DETAILS/RESULTS/ACTIONS
Is the fuse OK?
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8/16/2010