Ford Electric Ranger 2001 Manual page 309

412-02-15
DIAGNOSIS AND TESTING (Continued)
PINPOINT TEST F: DTC C1779 BLOWER SWITCH FAILURE
• With key OFF, measure the resistance between BOB pins 60, 61, 62 and
ground (BOB pin 80).
• Are the resistances greater than 10,000 ohms?
F6 CHECK CIRCUITS 751 (DB/W), 752 (Y/R), AND 754 (LG/W) FOR
SHORT(S) TO POWER
• With key ON, measure the voltage between BOB pins 60, 61, 62 and
ground (BOB pin 80).
• Are any of the voltages greater than 0 volts?
F7 CHECK BLOWER SWITCH
• With key OFF, disconnect blower switch C232 and check the continuity
of the blower switch by measuring the resistance between the circuit 57
(BK wire) terminal and the indicated terminals on the blower switch.
Compare the readings to the values below:
Low Blower Position
— Circuit 751 (DB/W wire) terminal = Open
— Circuit 752 (Y/R wire) terminal = Open
— Circuit 754 (LG/W wire) terminal = Open
Medium Blower Position
— Circuit 751 (DB/W wire) terminal = Closed
— Circuit 752 (Y/R wire) terminal = Open
— Circuit 754 (LG/W wire) terminal = Open
Medium-High Blower Position
— Circuit 751 (DB/W wire) terminal = Closed
— Circuit 752 (Y/R wire) terminal = Closed
— Circuit 754 (LG/W wire) terminal = Open
High Blower Position
— Circuit 751 (DB/W wire) terminal = Open
— Circuit 752 (Y/R wire) terminal = Closed
— Circuit 754 (LG/W wire) terminal = Closed
• Is the blower switch OK?
PINPOINT TEST G: DTC C1780 TEMPERATURE SELECT FAILURE
G1 CHECK TEMPERATURE CONTROL OPERATION
• With key ON, monitor the interface adapter assembly (IAA) module PID
SET TMP while rotating the temperature control knob from the full
cool position to the full warm position.
• Does the SET TMP PID indicate approximately 98% at the full
cool position and approximately 1% at the full warm position?
G2 CHECK TEMPERATURE CONTROL VOLTAGE REFERENCE
• With key OFF, disconnect temperature control C231.
• With key ON, measure the voltage between the LG/O wire and Y/LG
wire on temperature control C231.
• Is the voltage between 4.8 and 5.2 volts?
G3 CHECK CIRCUITS 3057 (LG/O) AND 3059 (Y/LG) FOR OPEN(S)
• Connect 104-Pin Breakout Box (BOB) to IAA module C1945; leave IAA Yes =
module disconnected.
(Continued)
Heating and Ventilation
TEST STEP
TEST STEP
ACTION TO TAKE
Yes = GO to F6.
No = REPAIR the wire(s) in
question.
Yes = REPAIR the wire(s) in
question.
No = REPLACE the IAA module.
REFER to Section
Yes = REPLACE the IAA module.
REFER to Section
No = REPLACE the blower
switch.
ACTION TO TAKE
Yes = System OK. CHECK wiring
for intermittent connections.
GO to G2.
No =
GO to G5.
Yes =
No = GO to G3.
GO to G4.
2001 Ranger EV, 01/2001
412-02-15
412-04.
412-04.