Ford 2001 Ranger, Manual

Page: 228 / 1218

303-03-7 303-03-7 Engine Cooling
DIAGNOSIS AND TESTING (Continued)
PINPOINT TEST B: COOLANT PUMP DOES NOT OPERATE
TEST STEP ACTION TO TAKE
•
With key OFF, disconnect coolant pump C1998. Yes = REPLACE the coolant
pump.
•
Enter the IAA module active command mode CLIMATE SYSTEM No = GO to B4.
CONTROL, set the active command PUMP/VBC to ON, and measure
the voltage between the W/R wire and BK wire on coolant pump C1998.
•
Is the voltage greater than 10 volts?
B4 CHECK GROUND TO COOLANT PUMP
•
With key OFF, measure the resistance between the BK wire on coolant Yes = GO to B5.
pump C1998 and ground.
•
Is the resistance less than 5 ohms?
No = REPAIR the BK wire.
B5 CHECK COOLANT PUMP RELAY CONTROL CIRCUIT
•
With key OFF, remove the coolant pump relay from the EVPDB. Yes = GO to B7.
•
Enter the IAA module active command mode CLIMATE SYSTEM No = GO to B6.
CONTROL, set the active command PUMP/VBC to ON, and measure
the resistance between pin 86 on the coolant pump relay connector and
ground.
•
Is the resistance less than 5 ohms?
B6 CHECK CIRCUIT 3020 (LB) FOR OPEN
•
Connect 104-Pin Breakout Box (BOB) to IAA module C1945; leave IAA Yes = REPLACE the IAA module.
module disconnected. REFER to Section 412-04.
•
With key OFF, measure the resistance of the LB wire between pin 86 on No = REPAIR the LB wire.
the coolant pump relay connector and BOB pin 19.
•
Is the resistance less than 5 ohms?
B7 CHECK CIRCUIT 3229 (W/R) FOR OPEN
•
With key OFF, measure the resistance of the W/R wire between coolant Yes = REPLACE the coolant pump
pump C1998 and pin 30 on the coolant pump relay connector. relay.
•
Is the resistance less than 5 ohms?
No = REPAIR the W/R wire.
PINPOINT TEST C: COOLANT PUMP RUNS WITH THE IGNITION KEY IN THE OFF POSITION
TEST STEP ACTION TO TAKE
C1 CHECK CIRCUIT 3229 (W/R) FOR SHORT TO POWER
•
Remove the coolant pump relay from the electric vehicle power Yes = GO to C2.
distribution box (EVPDB).
•
Does the coolant pump stop running?
No = REPAIR the W/R wire.
C2 CHECK COOLANT PUMP RELAY
•
Measure the resistance between terminals 30 and 87 on the coolant pump Yes = REPLACE the coolant pump
relay. relay.
•
Is the resistance less than 5 ohms?
No = GO to C3.
C3 CHECK CIRCUIT 3020 (LB) FOR SHORT TO GROUND
•
With key OFF, disconnect interface adapter assembly (IAA) module Yes = REPLACE the IAA module.
C1945 and measure the resistance between pin 86 on the coolant pump REFER to Section 412-04.
relay connector and ground.
•
Is the resistance greater than 10,000 ohms?
No = REPAIR the LB wire.
PINPOINT TEST D: COOLING FAN DOES NOT OPERATE
TEST STEP ACTION TO TAKE
D1 CHECK FUSE AND POWER TO FAN SPEED RELAYS
•
Check 50A fuse 5 in the electric vehicle power distribution box Yes = RECONNECT the fan speed
(EVPDB). relays. GO to D2.
(Continued)
2001 Ranger EV, 01/2001