BLOWER MOTOR VIBRATION
Possible causes of blower motor vibration include:
* Improper blower motor mounting.
* Improper blower wheel or fan mounting.
* Blower wheel or fan out of balance.
* Blower motor faulty.
BLOWER MOTOR NOISE
Possible causes of blower motor noise include:
* Foreign material in blower motor housing.
* Foreign material in A/C-heater housing.
* Improper blower motor mounting.
* Improper blower wheel or fan mounting.
* Blower motor faulty.
VACUUM CONTROL SYSTEM DIAGNOSIS
VACUUM CONTROL ONE-WAY CHECK VALVE
NOTE: Some models use brake booster check valve for vacuum source.
These models do not use another in-line vacuum check valve.
1) In engine compartment, locate Black vacuum hose that runs
from brake booster check valve or intake manifold, through firewall
near heater hoses or expansion valve. This supply vacuum hose goes to
A/C-heater control panel vacuum switch.
2) Within Black vacuum hose, disconnect and remove check
valve near intake manifold or brake booster. Connect vacuum gauge to
an external vacuum pump. Start vacuum pump. Plug end of hose probe on
vacuum gauge. Adjust bleed valve on vacuum gauge to obtain an exact
vacuum reading of 8 in. Hg.
3) Unplug and plug end of hose probe on vacuum gauge several
times to ensure exact vacuum reading. Connect vacuum gauge hose probe
to control panel side of check valve. Vacuum gauge reading should be 8
in. Hg. Replace check valve if vacuum leak exists.
4) Connect vacuum gauge hose probe to engine side of check
valve. Vacuum should flow through check valve. Replace check valve if
operation is not as described.
VACUUM CONTROLS
1) This test checks for proper function of control panel
vacuum circuits. Perform steps 1) through 4) under VACUUM CONTROL ONE-\
WAY CHECK VALVE.
2) Connect vacuum gauge hose probe to Black vacuum hose end
that leads to A/C-heater control panel switch. Position vacuum gauge
so gauge reading can be observed from inside vehicle.
3) Operate A/C-heater controls (sliding lever or push
buttons) in all mode positions (floor, defrost, panel, etc.). Pause
after each selection to allow vacuum actuators or motors to energize
and stabilize. Record vacuum gauge reading at each selection.
4) After each selection, vacuum reading should be 7.5-8 in.
Hg. Maximum vacuum reading drop is .75 in. Hg. If proper vacuum
reading cannot be obtained, vacuum leak exists in selected circuit.
5) To check for vacuum leak(s), disconnect 7-way A/C-heater
control panel vacuum harness connector. See Fig. 1. If necessary,
remove control panel from instrument panel to access A/C-heater
control panel vacuum harness connector, or remove lower instrument
BLOWER MOTOR VIBRATION
Possible causes of blower motor vibration include:
* Improper blower motor mounting.
* Improper blower wheel or fan mounting.
* Blower wheel or fan out of balance.
* Blower motor faulty.
BLOWER MOTOR NOISE
Possible causes of blower motor noise include:
* Foreign material in blower motor housing.
* Foreign material in A/C-heater housing.
* Improper blower motor mounting.
* Improper blower wheel or fan mounting.
* Blower motor faulty.
VACUUM CONTROL SYSTEM DIAGNOSIS
VACUUM CONTROL ONE-WAY CHECK VALVE
NOTE: Some models use brake booster check valve for vacuum source.
These models do not use another in-line vacuum check valve.
1) In engine compartment, locate Black vacuum hose that runs
from brake booster check valve or intake manifold, through firewall
near heater hoses or expansion valve. This supply vacuum hose goes to
A/C-heater control panel vacuum switch.
2) Within Black vacuum hose, disconnect and remove check
valve near intake manifold or brake booster. Connect vacuum gauge to
an external vacuum pump. Start vacuum pump. Plug end of hose probe on
vacuum gauge. Adjust bleed valve on vacuum gauge to obtain an exact
vacuum reading of 8 in. Hg.
3) Unplug and plug end of hose probe on vacuum gauge several
times to ensure exact vacuum reading. Connect vacuum gauge hose probe
to control panel side of check valve. Vacuum gauge reading should be 8
in. Hg. Replace check valve if vacuum leak exists.
4) Connect vacuum gauge hose probe to engine side of check
valve. Vacuum should flow through check valve. Replace check valve if
operation is not as described.
VACUUM CONTROLS
1) This test checks for proper function of control panel
vacuum circuits. Perform steps 1) through 4) under VACUUM CONTROL ONE-\
WAY CHECK VALVE.
2) Connect vacuum gauge hose probe to Black vacuum hose end
that leads to A/C-heater control panel switch. Position vacuum gauge
so gauge reading can be observed from inside vehicle.
3) Operate A/C-heater controls (sliding lever or push
buttons) in all mode positions (floor, defrost, panel, etc.). Pause
after each selection to allow vacuum actuators or motors to energize
and stabilize. Record vacuum gauge reading at each selection.
4) After each selection, vacuum reading should be 7.5-8 in.
Hg. Maximum vacuum reading drop is .75 in. Hg. If proper vacuum
reading cannot be obtained, vacuum leak exists in selected circuit.
5) To check for vacuum leak(s), disconnect 7-way A/C-heater
control panel vacuum harness connector. See Fig. 1. If necessary,
remove control panel from instrument panel to access A/C-heater
control panel vacuum harness connector, or remove lower instrument
CRUIS E C O NTR O L S YSTE M
1999 D odge P ic ku p R 1500
1999 ACCESSORIES & EQUIPMENT
CHRY - Cruise Control Systems
Dakota, Durango, Ram Pickup, Ram Van & Ram Wagon
CAUTION: When battery is disconnected, vehicle computer and memory
systems may lose memory data. Driveability problems may exist
until computer systems have completed a relearn cycle. See
COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION
before disconnecting battery.
DESCRIPTION
The speed (cruise) control system is electronically
controlled and vacuum operated. The electronic control is integrated
into the Powertrain Control Module (PCM). System consists of the
following components: Powertrain Control Module (PCM), servo, speed
control switches, vacuum reservoir, vehicle speed sensor, speed
control relay and brake switch.
System controls are located on each side of steering wheel
air bag module and consist of ON/OFF, SET, RESUME/ACCEL, CANCEL AND
COAST buttons. System is designed to operate at speeds above 30 MPH.
OPERATION
SYSTEM CONTROLS
To Set Speed Control
Press ON/OFF button to turn speed control system on.
Accelerate to desired speed (minimum of 35 MPH) and press SET/COAST
button. Vehicle speed will be maintained.
NOTE: Speed control system will automatically disengage when
vehicle speed decreases to less than 35 MPH or increases to
more than 85 MPH.
To Disengage Speed Control
Press brake pedal. Press clutch pedal (M/T). Press CANCEL
button. Press ON/OFF button. If ON/OFF button is used, set speed will
be erased from memory.
To Resume Previous Speed
If set speed has not been erased from memory and vehicle
speed is more than 35 MPH, press RES/ACCEL button.
To Increase Speed
With speed control system on, increase set speed by rapidly
pressing and releasing RES/ACCEL button. Each pressing of button will
cause speed increase of 2 MPH. For example, pressing button 3 times
will increase speed by 6 MPH. To increase speed gradually, hold
RES/ACCEL button down until desired speed is reached. When button is
released, new set speed will be maintained.
To Decrease Speed
With speed control system on, decrease set speed by pressing
SET/COAST button. Vehicle speed will gradually decrease. Releasing
button will set a new speed as long as vehicle speed is still more
than 35 MPH.
PCM controls operation of electric cooling fan. PCM operates fan
through radiator fan relay by grounding or ungrounding relay control
circuit. PCM regulates engine idle speed through IAC motor when fan is
on.
SHIFT INDICATOR LIGHT
PCM provides ground for shift indicator light on models
equipped with manual transmission. Based on engine speed, throttle
position, and vehicle speed, PCM turns shift indicator light on to
advise driver to shift to a higher gear for optimum fuel economy.
SPEED CONTROL SERVO
System is electrically actuated and vacuum operated. Controls
are located on steering wheel. Controls consist of 3 buttons: OFF/ON,
RESUME/ACCEL and SET/DECEL. Speed control servo is controlled by PCM.
System will operate at 35-85 MPH.
TACHOMETER
PCM provides signal to drive tachometer.
TORQUE CONVERTER CLUTCH (TCC) SOLENOID
PCM controls torque converter lock-up through TCC solenoid.
PCM controls lock-up according to various operating conditions.
TRANSMISSION GOVERNOR SOLENOID
PCM controls solenoid to regulate line pressure for shift
control.
TRANSMISSION OVERDRIVE/OVERRIDE (OD/OR) SWITCH INDICATOR
LIGHT
PCM controls indicator light on OD/OR switch on models
equipped with overdrive automatic transmission.
TRANSMISSION OVERDRIVE (OD) SOLENOID
On models equipped with OD transmission, PCM controls 3-4 OD
upshift and downshift through OD solenoid. PCM determines optimum OD
shift scheduling for all operating conditions.