HONDA PRELUDE 1990 Service Manual

Heating and Cooling
The vents, heater and air conditioner are combined in one system; adjusting four basic controls to different settings can provide a fullrange of interior temperatures for safe and comfortable driving,
(Air conditioner is optional on the 2.0 S and 2.0 Si models.)
Ventilation
The flow-through ventilation system can provide fresh air to theinterior when the car is moving or stopped, even with the sunroof
and windows closed.

NOTE:

For proper air flow, the flow-through vents must not be covered.
Keep the air inlet at the base of the windshield free of leaves or
other debris.
You can adjust the controls to direct cool or warm outside air
throughout the car for defogging windows, heating, or cooling by
turning on the fan.

(cont'd)

AIR INLET

AIR OUTLET
AIR OUTLETProCarManuals.comMain Menu t s

Heating and Cooling (cont'd)
Dash Vents
The side and center vents can be tilted up or down, and their
louvers turned right or left, to change the direction of air flow.
SIDE DEFROSTER
OUTLET
SIDE VENT
WINDSHIELD DEFROSTER
OUTLETS

SIDE DEFROSTER
OUTLET
FLOOR OUTLETS SIDE VENTS
CENTER VENTSProCarManuals.comMain Menu t s

What the Controls Do:

FUNCTION BUTTONS
AND INDICATOR LIGHTS RECIRCULATION BUTTON
AND INDICATOR LIGHT FRESH AIR BUTTON
AND INDICATOR LIGHT

FAN SWITCH

TEMPERATURE LEVER AIR CONDITIONER SWITCH
AND INDICATOR LIGHT COMPRESSOR LIGHT

Fan Switch

Turning the dial clockwise will increase the fan speed, and the fan
will circulate warm, cool, or outside air, depending on where the
temperature lever and function buttons are set.
Function Buttons

Push the appropriate button to direct air to and from the heater,
defroster and vents. Each function button has an indicator light that
comes on when the button is pushed in.
Air Conditioner Switch (optional on the 2.0 S and 2.0 Si models)
With the fan on, push the A/C switch to operate the air conditioner;
the indicator light will come on.
Push the switch again to turn the air conditioner off.
NOTE:
If the air conditioner compressor light comes on, turn off the A/C
switch (with the engine running) and turn it on again. If the light does
not come on again, the system is functioning normally, if the light
does come on again, turn off the A/C switch and do not use the
system until it can be checked by an authorized Honda dealer.
Temperature Lever Slide the lever from left to right to make air warmer when the
appropriate function is selected. and Recirculation
Fresh Air
When the
Buttons

button is pushed, the indicator light will go on and
outside air will be allowed to circulate inside the car.
When the outside air is shut off, and the air inside the car is recirculated. So,
when the heater or air conditioner is on and you want to warm up
or cool down the interior more quickly, or keep smoke or dust out
of the car without losing the heat or cool function, simply push the
button.
button is pushed, the indicator light comes on,ProCarManuals.comMain Menu t s

Heating and Cooling (cont'd)

NOTE:

The windows may become fogged if the system is in the
position for an extended period of time with the air

conditioner off. As soon as the interior is warmed, switch to the
position.
How to Use the Controls
To Ventilate Move the temperature lever to the left, and push the buttons. Turn the fan switch on and outside air will flow
through the side and center vents. To change air distribution, select
To Cool with A/C (optional on the 2.0 S and 2.0 Si models)
To cool the car down quickly, start the engine, then turn the fanswitch to high, push the A/C button on and open the windows briefly. Then close the windows, slide the temperature lever to the
When the interior has cooled desired speed, then push the (outside) air to the air conditioner.
When using the air conditioner in heavy traffic, or while driving up long hills, watch the coolant temperature gauge: if the needle movesnear the "H" end of the scale, turn the air conditioner off by
pushing the A/C button ; leave it off until the needle goes back well
into the middle of the scale.
and

the
ducts at the floor level. position and outside air will also flow from the heater
sufficiently, switch the fan to thebutton to direct fresh

and

left, push the
recirculate to the buttons, so inside air will
air conditioner for maximum cooling.ProCarManuals.comMain Menu t s

To Heat
Switch the fan on, slide the temperature lever to the right, push the
button, and warmed (outside) air will begin flowing from
the floor outlet.
Selecting the
direct a small amount of air through the dash vents in addition to the
floor outlets. button, will
button instead of the
To warm up the interior quickly, push in the inside air will recirculate to the heater. button so
position,
begin to fog while heating in the
to allow outside air to enter.
If the windows
switch to

To Defrost

To defrost or defog the windshield and
temperature lever to the right, push the door windows, slide the
(defrost) button,
switch on. Warmed
(outside) air will then flow from the windshield and side defroster

vents.
switch to the
setting, and turn the fanProCarManuals.comMain Menu t s

Heating and Cooling (cont'd)

To Dehumidify with A/C(optional on the 2.0 S and 2.0 Si models) Because an air conditioner dehumidifies as it works, you can use it
in cool or cold weather to help defog the windows. Just switch the
fan on, push the A/C button on, select the desired function and
adjust the temperature lever to a comfortable setting.
NOTE:
This setting is desirable for most operating conditions in ambient
temperatures above approximately 32°F (0°C).
To Turn Everything OFFSlide the temperature lever to the left, turn the fan switch off and push the

NOTE:

This setting should only be used in cold weather for the first few minutes of driving to prevent cold air from blowing into the cabin.
Under normal operating conditions, the fan should always be kept
ON to prevent the accumulation of stale air in the system. button on.ProCarManuals.comMain Menu t s

Stereo Sound System
(2.0 SI2.0 Si)
Bass Control

(Si) Bass Contro
l
ON/OFF Switch
On the 2.0 S and 2.0 Si models:
Turn the switch clockwise to turn the unit on, to increase volume and to raise the power antenna; turn it counterclockwise to
decrease volume, to turn the unit off and to retract the antenna.
The antenna will also retract automatically if the ignition is switched off.
On the Si model:
Push the button to turn the unit on and to raise the power antenna; push it again to turn it off and to retract the antenna. The antenna
will also retract automatically if the ignition is switched off. Volume Control

On the 2.0 S and 2.0 Si models:

Turn the ON/OFF switch clockwise to increase volume and
counterclockwise to decrease volume. On the Si model:
Push the switch up to increase volume and down to decrease
volume.

(cont'd)

Treble Control
Treble ControlProCarManuals.comMain Menu t s

Stereo Sound System (cont'd)
(2.0 S/2.0 Si)
(Si)
NOTE:
When the headlights are on, the radio panel illumination is on, even if
the radio is turned off.
The panel lighting can be turned off by first pushing the BalanceControl button to its out position and then pulling it out slightly

further.
Fader Control
Balances sound between front and rear speakers.
Radio Operation AM/FM Band Selector
Push to select AM or FM band. The corresponding band indicator
will light. Manual Tuning
Push the button to tune to a lower frequency station.
Push the button to tune to a higher frequency station.
NOTE:

If you

hold either button in for more than half a second, the tuning
frequency will count up or down rapidly. Balance Control

Balances sound between left and right speakers.
Frequency

Display
Frequency

DisplayProCarManuals.comMain Menu t s

Seek Tuning
Each time you push this button up or down, the tuner will
automatically seek the next higher or lower frequency station. Preset Station Selection
1 .Select AM or FM band by depressing the Band Selector. Find the station you want by Manual Tuning or Seek Tuning.
Press and hold one of the Preset Buttons.
2. In a few seconds, a beep will sound and the light in the button will
3. come on. The station is now preset in the memory. You may preset 1 AM and 1 FM station per button.
(total, 6 of each on the 2.0 S and 2.0 Si models and 8 of each on
the Si model).
4. You can tune to a preset station by pushing its corresponding preset button.

NOTE: On the Si model

The Auto Preset button must be off before the Preset Station Selection can be used. Auto Select Button (Si only)
If you are visiting a new broadcast area, you can quickly enter into
memory the stronger stations in that area by simply pushing the
Auto Select Button. The radio will then automatically scan the AM
and FM bands and temporarily memorize up to eight stations in each.
With the Auto Select Button on, these stations can then be tuned by pushing the preset buttons. Manually-preset stations remainmemorized for use when you return to your normal broadcast area,
but are only selectable with the Auto Select Button off. Stereo indicator
This lights up when an FM broadcast in stereo is being received. It will flash when the signal strength diminishes. If it flashes, good
stereo reception cannot be expected. Stereo reception is available
only for FM stereo broadcasts, not for AM stereo broadcasts.

(cont'd)ProCarManuals.comMain Menu t s

Stereo Sound System (cont'd)
(2.0 S/2.0 Si)
(Si) Tape Direction Indicator
With the cassette inserted "A" side up, the indicator ( ) will light
when the "A" side is playing; the indicator ( ) will light when the
"B" side is playing. Program Selector (PROG)
Push to change the direction of tape play.
Auto Reverse Feature: The tape direction automatically reverses when the end of the tape is reached in Play or FF mode and plays
the other side. Fast Forward/Rewind (FF/REW)
Note which Tape Direction Indicator is lighted, then push the
appropriate button to rapidly wind the tape in the same direction (FF) or in the opposite direction (REW) Play (PLAY)
Push the PLAY button (indicator on) to resume tape play and stop
rewind or fast forward operation. Tape OperationProCarManuals.comMain Menu t s