Pontiac Fiero 1988 Service Manual page 34

HEATING AND VENTILATION 1A-9
4 >TOO MUCH HEAT
HEATER MODE VENT MODE
— —
ADJUST THE HEATER CON-
TROLS TO: HEATER MODE,
HIGH BLOWER SPEED,
TEMPERATURE LEVER
TO FULL HOT
WITH THE IGNITION
SWITCH ON, CHECK FOR
AIRFLOW OUT OF THE
HEATER OUTLET &
CHECK OUTLET
ATTACHMENT
I —
OBJECTIONABLE
BLEED
I
CHECK FOR
SYSTEM CASE
LEAKS &
CHECK HEAT-
ER OUTLET
ATTACHMENT
HIGH
AIRFLOW
LOW OR
NO
AIRFLOW
CHECK
BLOWER
SPEEDS
FOR
AIRFLOW
CHANGE
CHECK
BLOWER
SPEEDS
FOR
AIRFLOW
CHANGE
I
VENT AIR
TOO WARM
OBJECTIONABLE
DEFROSTER BLEED
WITH THE IGNI-
TION SWITCH
OFF, MOVE THE
TEMPERATURE
LEVER TO FULL
HOT THEN RAP-
DLY TO FULL
COLD, LISTEN
FOR DOOR SLAM
PRIOR TO
CONTROL END
OF TRAVEL
CHECK THE HEATER &
DEFROSTER DOOR
ADJUSTMENTS, CA-
BLES, CONTROLS,
LINKAGE & ADJUST
AS REQUIRED.
WITH THE IGNITION
SWITCH OFF, MOVE THE
TEMPERATURE LEVER TO
FULL HOT THEN RAPIDLY
TO FULL COLD. LISTEN
FOR DOOR SLAM PRIOR
TO CONTROL END OF
TRAVEL.
SPEED
CHANGE
OK
NO
SPEED
CHANGE
<S>
SPEED
CHANGE
OK
CHECK THE TEM-
PERATURE DOOR
ADJUSTMENT, CA-
BLES, LINKAGE &
ADJUST TO FULL
COLD, CHECK FOR
FULL HOT.
ADJUST THE
HEATER DE-
FROSTER
AND/OR VENT
DOOR TO
HEATER
MODE.
DOOR SLAM
OK
NO DOOR
SLAM
| ~ " N O DOOR SLAM | | DOOR SLAM OK
CHECK THE
TEMPERATURE
DOOR ADJUSTMENT,
CABLES, LINKAGE &
ADJUST TO FULL
COLD. CHECK FOR
FULL HOT.
ADJUST THE CON-
TROLS TO VENT
MODE, HIGH BLOWER
SPEED & THE TEMP-
ERATURE LEVER TO
FULL COLD. START
THE VEHICLE & AL-
LOW THE ENGINE
TO WARM UP WITH
A THERMOMETER,
CHECK THE AIR
TEMPERATURE AT
THE BLOWER INLET
(COWL) & AT THE
VENT AIR OUTLET IN
THE VEHICLE. THE
TEMPERATURE DIF-
FERENCE IS THE A T.
CHECK THE TEMPER-
ATURE DOOR AD-
JUSTMENT, CABLES,
LINKAGE & ADJUST
TO FULL COLD.
CHECK FOR
FULL HOT.
A T 5°C(10°F)
OR LESS
ADJUST THE
HEATER DEFROST-
ER & VENT DOOR
TO VENT MODE
SYSTEM OK
A T MORE THAN 5°C(10°F)
CHECK FOR HOT AIR
LEAKS FROM THE ENGINE
COMPARTMENT TO THE
BLOWER INLET & REPAIR
AS NECESSARY
G20026-1A
Figure 10 Too Much Heat Diagnosis