Chrysler Dodge Caravan 2002 Manual page 2250

RS
HEATING & AIR CONDITIONING (Continued)
If coolant flow is verified and the heater floor out-
let temperature is insufficient, a mechanical problem
may exist.
POSSIBLE LOCATION OR CAUSE OF INSUFFICIENT HEAT
• Obstructed cowl air intake.
• Obstructed heater system outlets.
• Blend-air door not functioning properly.
SPECIFICATIONS - HEATER-A/C SYSTEM
ITEM
Vehicle
System
Compressor
Freeze–up Control
Low PSI Control
High PSI Control
Control Head
Mode Door
Blend Air Door
Fresh/Recirc Door
Blower Motor
Cooling Fans
Clutch
Clutch Control
Clutch Coil Draw
Compressor Clutch Air Gap
Diagnostics
DESCRIPTION
RS - Caravan, Town & Country, Voyager
R134a with expansion valve(s)
Nippondenso - 10S20
evaporator temperature sensor
pressure transducer
pressure relief valve
single zone, dual zone, and three zone
Manual Temperature Control (MTC) - or three
zone Automatic Temperature Control (ATC)
electric actuator
electric actuator
electric actuator
control head switch
pulse width modulated variable speed
PCM
2.2 amps @ 12V
0.020 - 0.035
DRBIII scan tool
HEATING & AIR CONDITIONING
TEMPERATURE CONTROL
If heater floor outlet temperature cannot be
adjusted with the heater-A/C control temperature
control lever, one of the following could require ser-
vice:
• Blend-air door binding.
• Faulty blend-air door motor.
• Improper engine coolant temperature.
• Faulty heater-A/C control.
ND-8 PAG Oil
expansion valve mounted - input
to heater-A/C control module
liquid line mounted - input to
Powertrain Control Module (PCM)
- PCM opens compressor clutch
relay < 29.4 psi
liquid line mounted - input to
PCM - PCM opens compressor
clutch relay > 450 psi
compressor mounted - opens >
495 psi
PCI data bus messaging - ATC
uses three infrared temperature
sensors - two front/one rear
Control head driven
resistor and relay with MTC,
power module and relay with ATC
PCM control through solid state
fan relay
PCM control through compressor
clutch relay
± 0.5amps@ 70° F
24 - 7
NOTES