Ford Electric Ranger 2001 Manual page 308

412-02-14
DIAGNOSIS AND TESTING (Continued)
PINPOINT TEST E: DTC C1776 HEATER SYSTEM FAILURE
• Is the resistance greater than 10,000 ohms?
E16 CHECK SYSTEM
• With key OFF, reconnect all component connectors that were
disconnected.
• With key ON, set the mode select knob to the PANEL/FLOOR position,
the temperature control knob to the full warm position, and the blower
control knob to the HIGH speed position.
• Does the 25A PTC HTR high-voltage fuse fail again?
E17 INSPECT PTC HEATER CORES
• Remove the PTC heater core and check for contaminants (excessive
moisture or debris) on the heater core.
• Is the heater core clear of contaminants?
PINPOINT TEST F: DTC C1779 BLOWER SWITCH FAILURE
F1 CHECK BLOWER SWITCH STATUS
• With key ON, monitor the interface adapter assembly (IAA) module PID
BLOWER while rotating the blower control knob through all the blower
speed positions.
• Does the BLOWER PID agree with all the blower speed positions?
F2 CHECK BLOWER SWITCH INPUT VOLTAGE REFERENCES
• Connect 104-Pin Breakout Box (BOB) to IAA module and IAA module
C1945.
• With key ON, measure the voltage between BOB pins 60, 61, 62 and
ground (BOB pin 80).
• Do the voltages fluctuate between 0 and 2.8 volts?
F3 CHECK GROUND TO BLOWER SWITCH
• With key OFF, disconnect blower switch C232 and measure the
resistance between the BK wire on blower switch C232 and ground.
• Is the resistance less than 5 ohms?
F4 CHECK CIRCUITS 751 (DB/W), 752 (Y/R), AND 754 (LG/W) FOR
OPEN(S)
• With key OFF, disconnect IAA module from BOB; leave BOB
connected to IAA module C1945.
• With key OFF, measure the resistance of the DB/W wire between blower No =
switch C232 and BOB pin 62.
• With key OFF, measure the resistance of the Y/R wire between blower
switch C232 and BOB pin 61.
• With key OFF, measure the resistance of the LG/W wire between blower
switch C232 and BOB pin 60.
• Are the resistances less than 5 ohms?
F5 CHECK CIRCUITS 751 (DB/W), 752 (Y/R), AND 754 (LG/W) FOR
SHORT(S) TO GROUND
(Continued)
Heating and Ventilation
TEST STEP
TEST STEP
ACTION TO TAKE
No = REPLACE the HVPDB.
REFER to Section 414-03A
or Section 414-03B.
Yes = REPLACE the PTC
switching module.
REPLACE the 25A PTC
HTR fuse. REFER to
Section 414-03A
Section 414-03B.
No = System OK.
Yes = REPLACE the PTC
switching module.
No = REMOVE the contaminants.
If necessary, REPLACE the
PTC heater core.
ACTION TO TAKE
Yes = System OK. CHECK wiring
for intermittent connections.
No = GO to F2.
GO to F7.
Yes =
GO to F3.
No =
GO to F4.
Yes =
No = REPAIR the BK wire.
GO to F5.
Yes =
REPAIR the wire(s) in
question.
2001 Ranger EV, 01/2001
412-02-14
or