Ford 2001 Ranger, Manual

Page: 320 / 1218

412-02-26 412-02-26 Heating and Ventilation
DIAGNOSIS AND TESTING (Continued)
PINPOINT TEST Q: VACUUM PUMP CYCLES ON AND OFF WITHOUT BRAKE PEDAL ACTIVATION
(CLIMATE CONTROL VACUUM SYSTEM LEAK TEST)/INCORRECT AIRFLOW THROUGH CLIMATE
CONTROL OUTLETS
TEST STEP ACTION TO TAKE
Q2 CHECK CLIMATE CONTROL VACUUM RESERVOIR SUPPLY
LINE CONNECTION
•
Check the vacuum supply line to the climate control vacuum reservoir Yes = GO to Q3.
for a secure connection.
•
Is the vacuum supply line securely connected?
No = RECONNECT the vacuum
supply line.
Q3 CHECK VACUUM RESERVOIR CHECK VALVE
•
Disconnect the vacuum lines from the vacuum reservoir. Yes = RECONNECT the vacuum
lines. GO to Q4.
NOTE: Vacuum should remain constant when applied to the vacuum
No = REPLACE the climate
reservoir port for the vacuum line leading to the passenger compartment
control vacuum reservoir.
and there should be no vacuum when applied to the port for the vacuum
line leading to the vacuum tee assembly. Airflow through the check valve
should be in the direction towards the vacuum pump.
•
Use Vacuum Tester to apply 103 kPa (15 psi) of vacuum to both ports
on the vacuum reservoir.
•
Is the vacuum reservoir check valve OK?
Q4 CHECK CLIMATE CONTROL VACUUM RESERVOIR FOR
VACUUM LEAK
•
With key ON, disconnect the vacuum line leading to the passenger Yes = RECONNECT the vacuum
compartment from the climate control vacuum reservoir and plug the port line to the vacuum reservoir.
on the vacuum reservoir. GO to Q5.
•
Monitor interface adapter assembly (IAA) module PID VACPRES for a No = REPLACE the climate
change in vacuum pressure after the vacuum pump shuts off. control vacuum reservoir.
•
Does the vacuum level remain constant?
Q5 CHECK VACUUM LINE TO PASSENGER COMPARTMENT
•
With key ON, disconnect the vacuum line in the passenger compartment Yes = RECONNECT the vacuum
located on the right side of the bulkhead and plug the port on the line to the bulkhead port.
bulkhead. GO to Q6.
•
Monitor IAA module PID VACPRES for a change in vacuum pressure No = REPLACE the vacuum line
after the vacuum pump shuts off. between the climate control
•
Does the vacuum level remain constant?
vacuum reservoir and
bulkhead.
Q6 CHECK BLACK VACUUM LINE TO MODE SELECT SWITCH
•
With key ON, disconnect the vacuum connector from the mode select Yes = RECONNECT the vacuum
switch and plug the black vacuum line on the vacuum connector. connector to the mode select
switch. GO to Q8.
•
Monitor IAA module PID module VACPRES for a change in vacuum No = GO to Q7.
pressure after the vacuum pump shuts off.
•
Does the vacuum level remain constant?
Q7 CHECK BLACK VACUUM LINE IN VACUUM JUMPER
HARNESS
•
With key ON, disconnect the vacuum jumper harness leading to the Yes = REPLACE the vacuum
heater plenum and plug the black vacuum line port on the heater plenum jumper harness.
vacuum connector.
•
Monitor IAA module PID VACPRES for a change in vacuum pressure No = REPLACE the heater
after the vacuum pump shuts off. plenum vacuum line
•
Does the vacuum level remain constant?
assembly.
Q8 CHECK MODE SELECT SWITCH
(Continued)
2001 Ranger EV, 01/2001