Ford F-150 1999 Workshop Manual page 22

1999 F-150/250 Workshop Manual
E5 CHECK CIRCUIT 399 (BR/Y) FOR A SHORT TO GROUND
A/C Blower Motor Relay
E6 CHECK CIRCUIT 364 (BK/LG) FOR A SHORT TO GROUND
E7 CHECK THE VOLTAGE TO THE A/C BLOWER MOTOR
A/C Blower Motor C190
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Measure the resistance between the A/C blower motor C190-2, Circuit 399 (BR/Y), and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to E6.
No
REPAIR Circuit 399 (BR/Y) for a short. TEST the system for normal operation.
Measure the resistance between the power distribution box Fuse 23 (40A) Pin 2, Circuit 364 (BK/LG) and ground.
Is the resistance greater than 10,000 ohms?
Yes
REPLACE the A/C blower motor relay. TEST the system for normal operation.
No
REPAIR Circuit 364 (BK/LG) for a short. TEST the system for normal operation.
Measure the voltage between A/C blower motor C190-2, Circuit 399 (BR/Y), and ground while selecting each
mode on the function selector switch.
Is the voltage greater than 10 volts in all function selector switch positions except OFF?
Yes
GO to E8.
No
Page 22 of 30
8/16/2010