coolant level MERCEDES-BENZ SPRINTER 2006 Workshop Manual

(12) Remove the camshaft housing at the cylinder
head (Fig. 14).
(13) Remove the high pressure pump.
(14) Remove the front head cover plate.
WARNING: NO FIRE, OPEN FLAMES OR SMOKING.
RISK OF POISONING FROM INHALING AND SWAL-
LOWING FUEL. RISK OF INJURY FROM SKIN AND
EYE CONTACT WITH FUEL. POUR FUELS ONLY
INTO SUITABLE AND APPROPRIATELY MARKED
CONTAINERS. WEAR PROTECTIVE CLOTHING
WHEN HANDLING FUEL.
(15) Remove the high pressure fuel pump interme-
diate gear (Fig. 14).
(16) Disconnect the engine side of the engine har-
ness and set aside.
(17) Disconnect the charge air pipe at the cylinder
head and set aside with the engine harness con-
nected.
(18) Remove the turbocharger oil supply line at
the cylinder head and turbocharger (Fig. 14).
(19) Disconnect the turbocharger at the exhaust
manifold (Fig. 14).(20) Unbolt the transmission oil level indicator
tube fasteners from the cylinder head and engine
block (Fig. 14).
(21) Disconnect the upper radiator hose and by
pass hose at the thermostat housing (Fig. 14).
NOTE: Capture any fuel spillage when disconnect-
ing fuel lines.
(22) Disconnect the fuel line at the rear of the fuel
rail (Fig. 14).
Fig. 14 CAMSHAFT HOUSING
1 - CAMSHAFT HOUSING 9 - HIGH PRESSURE PUMP INTERMEDIATE GEAR
2 - DOWEL 10 - EXHAUST MANIFOLD
3 - FUEL PIPE 11 - COOLANT PIPE
4 - O-RING 12 - TURBOCHARGER
5 - COOLANT HOSE 13 - O-RING
6 - COOLANT HOSE 14 - TURBOCHARGER OIL SUPPLY LINE
7 - BOLT 15 - BANJO BOLT
8 - BUSHING 16 - TAPPET
9 - 24 ENGINEVA

(2) Hand start clean head bolts and tighten per
the following procedure:
²Install M12 cylinder head bolts finger tight (Fig.
15).
²Tighten bolts in numeric order starting with
number 1 to 15 N´m (133 lbs.in.) (Fig. 17).
²Tighten bolts in numeric order starting with
number 1 to 60 N´m (44 lbs.ft.) (Fig. 17).
²Install M8 timing chain cover to cylinder head
bolts. Tighten to 20N´m (177 lbs.in.).
²Tighten M12 cylinder head bolts in numeric
order starting with number 1 an additional 90É (Fig.
17).
²Tighten M12 cylinder head bolts in numeric
order starting with number 1 an additional 90É again
(4 stages). (Fig. 17).
(3) Install fuel return flow line between rail and
high pressure pump (Fig. 14).
(4) Connect the coolant hoses to the thermostat
housing (Fig. 14).
(5) Connect the coolant pipe at the cylinder head
(Fig. 14).
(6) Reconnect transmission oil level indicator tube.
Tighten to 14 N´m (124 lbs. in.) (Fig. 14).
(7) Reconnect the turbocharger to the exhaust
manifold. Tighten to 30N´m (22 lbs.ft.) (Fig. 14).
(8) Install oil return flow line with new seals at
turbocharger. Tighten bolt of supply line to turbo-
charger to 18N´m (160 lbs. in.) and bolt of supply line
to cylinder head to 9N´m (80 lbs. in.) (Fig. 14)
(9) Install charge air distribution pipe (Refer to 11
- EXHAUST SYSTEM/TURBOCHARGER SYSTEM -
INSTALLATION).
(10) Install and properly route the engine wiring
harness, making appropriate connections.
(11) Install high pressure fuel pump intermediate
gear (Fig. 14).(12) Install high pressure pump (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL INJEC-
TION PUMP - INSTALLATION).
(13) Install the camshaft housing with tappets to
cylinder head (Fig. 14).
(14) Install camshafts (Refer to 9 - ENGINE/CYL-
INDER HEAD/CAMSHAFT(S) - INSTALLATION).
(15) Install top guide rail (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - INSTALLATION).
(16) Install front cover at cylinder head (Refer to 9
- ENGINE/CYLINDER HEAD - INSTALLATION).
(17) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(18) Install fuel high pressure pipes and injectors
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
FUEL INJECTOR - INSTALLATION).
(19) Install timing chain tensioner with new gas-
ket. (Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLATION)
Tighten to 80N´m (59 lbs.ft.).
(20) Remove retaining lock for crankshaft/starter
ring gear.
(21) Install air intake tube at turbocharger (Refer
to 11 - EXHAUST SYSTEM/TURBOCHARGER SYS-
TEM - INSTALLATION).
(22) Install the fasteners retaining the front
exhaust pipe to the support bracket at the read of
the engine.
(23) Install the upper support bracket fastener.
(24) Install the lower turbo support bracket bolt.
(25) Install engine cover (Refer to 9 - ENGINE -
INSTALLATION).
NOTE: DO NOT pressure test cooling system until
engine has reached operating temperature.
(26) Refill cooling system with proper coolant mix-
ture to proper level (Refer to 7 - COOLING/ENGINE/
COOLANT - STANDARD PROCEDURE).
(27) Connect negative battery cable.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHES.
(28) Start engine and inspect for leaks. Care must
be taken to observe the fuel system warning (Refer to
14 - FUEL SYSTEM - WARNING)
Fig. 17 CYLINDER HEAD BOLT TORQUE
SEQUENCE
VAENGINE 9 - 27

CAUTION: Oil thread and head contact surfaces of
bolts that retain the crankshaft bearing caps;
tighten bolts from inside to outside, beginning at
the fit bearing. Rotate crankshaft to check clear-
ance.
(1) Install crankshaft.
CAUTION: The crankshaft bearing caps are num-
bered consecutively, beginning with the first crank-
shaft bearing cap at the front of the engine.
Attention must be paid to the way the crankshaft
bearing caps fit. If correctly installed, the lug, or
raised boss, on the crankshaft bearing cap is point-
ing to the left when viewed in the direction of travel
(intake side).
(2) Install the crankshaft bearing caps. Tighten
bolts in two stages. 55N´m (40.5 lbs. ft.), then 90É.
(3) Install the pistons (Refer to 9 - ENGINE/EN-
GINE BLOCK/PISTON & CONNECTING ROD -
INSTALLATION).
(4) Install the end cover (Refer to 9 - ENGINE/EN-
GINE BLOCK/CRANKSHAFT OIL SEAL - REAR -
INSTALLATION).
(5) Install the timing case cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(6) Install the engine (Refer to 9 - ENGINE -
INSTALLATION).
(7) Fill the crankcase with the correct engine oil,
to the proper level. Refer to the owners manual for
specifications.
(8) Fill the cooling system with the proper coolant,
to the proper level (Refer to 7 - COOLING/ENGINE/
COOLANT - STANDARD PROCEDURE).
(9) Connect the negative battery cable.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS, OR FAN. DO
NOT WEAR LOOSE CLOTHES.
(10) Start engine and inspect for leaks. Care must
be taken to observe the fuel system warning (Refer to
14 - FUEL SYSTEM - WARNING).
CRANKSHAFT OIL SEAL -
REAR
REMOVAL
This must be done with the transmission removed
from the vehicle.
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Drain the engine oil.NOTE: Loosen all of the oil pan bolts to assure that
the oil pan gasket is not damaged when removing
the rear main oil seal and end cover assembly.
NOTE: Inspect the oil pan gasket for damage. If the
oil pan gasket is damaged, remove the oil pan and
replace the oil pan gasket.
(4) Loosen the oil pan bolts.
(5) Remove the flywheel.
CAUTION: Care must be taken when removing the
rear main seal and adaptor assembly. Failure to do
so will result in damage to the oil pan gasket.
(6) Remove the rear main seal/adaptor retaining
bolts and carefully pry the adaptor from the crank-
case at the adaptor shoulders (Fig. 33).
VAENGINE 9 - 41

(19) Fill the cooing system with proper coolant, to
the proper level (Refer to 7 - COOLING/ENGINE/
COOLANT - STANDARD PROCEDURE).
(20) Connect negative battery cable.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS, OR FAN. DO
NOT WEAR LOOSE CLOTHES.
WARNING: (Refer to 14 - FUEL SYSTEM - WARN-
ING).
(21) Start the engine and inspect for leaks.
PISTON RINGS
STANDARD PROCEDURE - PISTON RING FIT-
TING
(1) Carefully clean the carbon from all ring
grooves. Oil drain openings in the oil ring groove and
pin boss must be clear. DO NOT remove metal from
the grooves or lands. This will change ring-to-groove
clearances and will damage the ring-to-land seating.
(2) Be sure the piston ring grooves are free of
nicks and burrs.
(3) Measure the ring side clearance with a feeler
gauge fitted snugly between the ring land and ring
(Fig. 43). Rotate the ring in the groove. It must move
freely around circumference of the groove.
RING SIDE CLEARANCE CHART
ITEM SPECIFICATION
Top Compression Ring 0.012 - 0.016 mm
(0.0047 - 0.0063 in.)
Second Compression
Ring0.05 - 0.09 mm
(0.0019 - 0.0035 in.)
Oil Control Ring 0.03 - 0.07 mm
(0.0011 - 0.0027 in.)
(4) Place ring in the cylinder bore and push down
with inverted piston to position near lower end of the
ring travel. Measure ring gap with a feeler gauge fit-
ting snugly between ring ends (Fig. 44).
RING GAP MEASUREMENT CHART
ITEM SPECIFICATION
Top Compression Ring 0.229 - 0.610 mm
(0.0090 - 0.0240 in.)
Second Compression
Ring0.483 - 0.965 mm
(0.0190 - 0.080 in.)
Oil Control Ring 0.254 - 1.500 mm
(0.010 - 0.060 in.)
(5) The oil control rings are symmetrical, and can
be installed with either side up. It is not necessary to
use a tool to install the upper and lower rails. Insert
oil rail spacer first, then side rails.
(6) Using a ring expander, install compression
rings with manufactures designation pointing toward
piston crown (Fig. 45).
Fig. 43 Measuring Piston Ring Side Clearance
1 - FEELER GAUGE
Fig. 44 Ring
1 - FEELER GAUGE
9 - 52 ENGINEVA

INSTALLATION
(1) Clean all sealing surfaces.
(2) Install the engine oil cooler to the timing case
cover with a new gasket. Tighten bolts to 14N´m (124
lbs. in.) (Fig. 51).
(3) Reconnect the coolant hoses and tighten
clamps.
(4) Install new oil filter and tighten oil filter cap to
25N´m ( 18 lbs. ft.) (Fig. 51).
(5) Refill cooling system.
(6) Start engine and inspect for leaks.
(7) Turn engine off and check engine oil level. Add
as necessary.
OIL FILTER
REMOVAL
(1) Unscrew the oil filter cap (Fig. 52)
(2) Remove clean and inspect cap gasket, replace
as necessary.
(3) Remove oil filter (Fig. 52).
INSTALLATION
(1) Inspect oil filter cap gasket, if all right, lubri-
cate with clean engine oil.
(2) Install oil filter.
(3) Screw oil filter cap to housing and tighten to
25N´m (18 lbs. ft.) (Fig. 52). Adjust oil level as neces-
sary.
OIL JET
DESCRIPTION
There are five oil jets installed in the engine block
(Fig. 53). These oil jets are used to cool and lubricate
the piston assemblies.
Fig. 51 ENGINE OIL COOLER
1 - OIL FILTER
2 - OIL FILTER COVER
3 - GASKET
4 - BOLT
5 - COOLANT HOSE
6 - ENGINE OIL COOLER
Fig. 52 ENGINE OIL COOLER
1 - OIL FILTER
2 - OIL FILTER COVER
3 - GASKET
4 - BOLT
5 - COOLANT HOSE
6 - ENGINE OIL COOLER
VAENGINE 9 - 57

REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Drain engine oil into a suitable, and appropri-
ately marked container.
(4) Remove engine mount to chassis nuts.
(5) Lower vehicle and install engine support.
(6) Remove the turbo charger heat shield to radia-
tor support bolts.
(7) Raise engine until the weight of the engine no
longer rests on the engine mounts.
(8) Raise and support the vehicle.
(9) Detach the front stabilizer bar at the front axle
and rotate it downward.
(10) Unplug the oil level sensor (Fig. 67).
(11) Remove the oil level sensor retaining screw,
oil level sensor and discard the O-ring (Fig. 67).
INSTALLATION
(1) Seat new O-ring on oil level sensor and lubri-
cate O-ring with clean engine oil (Fig. 67).
(2) Install the oil level sensor into the oil pan and
tighten screw to 124 lbs. in.(14N´m) (Fig. 67).
(3) Connect oil level sensor wiring harness connec-
tor (Fig. 67).
(4) Rotate front stabilizer bar upward and secure
to axle beam. Tighten to 22 lbs.ft. (30 N´m)
(5) Lower the vehicle.
(6) Lower the engine into the mounts.
(7) Remove engine support fixture.(8) Raise and support the vehicle.
(9) Tighten both engine mount to chassis nuts.
(10) Install and tighten oil drain plug.
(11) Lower vehicle and install the appropriate
engine oil.
INTAKE MANIFOLD
REMOVAL
WARNING: NO FIRE, SPARKS OR SMOKING.
STORE FUELS ONLY INTO SUITABLE AND APPRO-
PRIATELY MARKED CONTAINERS, AND WEAR
PROTECTIVE CLOTHING. (Refer to 14 - FUEL SYS-
TEM - WARNING).
WARNING: DO NOT OPEN THE COOLING SYSTEM
UNLESS THE COOLANT TEMPERATURE IS BELOW
90ÉC (194ÉF). OPEN RADIATOR CAP SLOWLY TO
RELEASE PRESSURE. STORE COOLANT ONLY
INTO SUITABLE AND APPROPRIATELY MARKED
CONTAINERS, WEAR PROTECTIVE CLOTHING AND
EYE PROTECTION.
(1) Disconnect the negative battery cable.
(2) Partially drain coolant from the radiator.
(3) Remove the engine cover (Refer to 9 - ENGINE
- REMOVAL).
(4) Remove the high pressure fuel lines (Fig. 68).
Fig. 67 OIL LEVEL SENSOR
1 - OIL PAN
2 - O-RING
3 - WIRING HARNESS
4 - BOLT
5 - OIL LEVEL SENSOR
VAENGINE 9 - 65

INSTALLATION
CAUTION: Care must be taken to closley inspect
the gasket area around the time case cover to cyl-
inder head gasket coolant port. If damage is found,
replace the cylinder head gasket. Failure to do so
may result in engine damage.
NOTE: Thoroughly clean all mating surfaces with
the appropriate solvents to assure that no grease or
oil is present during assembly.
(1) Inspect cylinder head gasket and oil pan gas-
ket. If damaged, replace.
(2) Replace the front crankshaft seal (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - FRONT - INSTALLATION).
(3) Install ancillary components to timing case
cover.
(4) Apply sealant to the marked surfaces with a
bead thickness of 1.5   0.5 mm (Fig. 74).
NOTE: Install timing cover within 10 minutes after
applying sealant. Do not spread sealant bead.
NOTE: Do not seal pressurized oil galleries to the
crankcase. Sealant applied at these points is
entrained by the oil flow and blocks the oil supply
passages.
(5) Position and install timing case cover. Tighten
bolts to 20 N´m (177 lbs in) (Fig. 73).(6) Install the M8 bolts of cylinder head on timing
case cover. Tighten bolts to 20 N´m (177 lbs in) (Fig.
73).
(7) Install timing chain tensioner with new seal
(Refer to 9 - ENGINE/VALVE TIMING/TMNG BELT/
CHAIN TENSIONER&PULLEY - INSTALLATION).
(8) Position and install the oil pan. Tighten M6
bolts to 9 N´m (80 lbs in) and M8 bolts to 20 N´m
(177 lbs in).
(9) Install belt /pulley vibration damper. Tighten
M8.8 bolt in two stages, 200N´m (147 lbs ft.) then
90É, M10.9 bolt 325N´m (240 lbs ft) then 90É.
(10) Remove the engine support fixture.
(11) Install generator (Refer to 8 - ELECTRICAL/
CHARGING/GENERATOR - INSTALLATION).
(12) Install the air conditioning compressor.
(13) Install the power steering pump.
(14) Install water pump (Refer to 7 - COOLING/
ENGINE/WATER PUMP - INSTALLATION).
(15) Connect coolant hose to oil-water heat
exchanger.
(16) Install high pressure fuel pump (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL PUMP -
INSTALLATION).
(17) Apply sealant to lower portion of, and install,
front cover to cylinder block. Tighten bolts to 20N´m
(177 lbs in) (Refer to 9 - ENGINE/CYLINDER HEAD
- INSTALLATION).
(18) Remove retaining lock for crankshaft/starter
ring gear.
(19) Tighten the oil drain plug to 30N´m (265 lbs
in).
(20) Install a new oil filter. tighten screw cap for
filter to 25N´m (221 lbs. in.).
(21) Install the accessory drive belt.
(22) Install the radiator assembly (Refer to 7 -
COOLING/ENGINE/RADIATOR - INSTALLATION).
(23) Install air intake hose.
(24) Fill coolant to the proper level, with the
proper coolant (Refer to 7 - COOLING/ENGINE/
COOLANT - STANDARD PROCEDURE).
(25) Fill the crankcase with the correct oil, to the
proper level. Refer to owners manual for specifica-
tions.
(26) Connect the negative battery cable.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHES.
CAUTION: DO NOT pressure test cooling system
until the engine reaches operating temperature.
Fig. 74 TIMING CHAIN COVER SEALING SURFACE
1 - TIMING CHAIN COVER
2 - SEALANT BEAD
VAENGINE 9 - 71

CAUSES OF BURNT FLUID
Burnt, discolored fluid is a result of overheating
which has three primary causes.
1. Internal clutch slippage, usually caused by low
line pressure, inadequate clutch apply pressure, or
clutch seal failure.
2. A result of restricted fluid flow through the
main and/or auxiliary cooler. This condition is usu-
ally the result of a faulty or improperly installed
drainback valve, a damaged oil cooler, or severe
restrictions in the coolers and lines caused by debris
or kinked lines.
3. Heavy duty operation with a vehicle not prop-
erly equipped for this type of operation. Trailer tow-
ing or similar high load operation will overheat the
transmission fluid if the vehicle is improperly
equipped. Such vehicles should have an auxiliary
transmission fluid cooler, a heavy duty cooling sys-
tem, and the engine/axle ratio combination needed to
handle heavy loads.
FLUID CONTAMINATION
Transmission fluid contamination is generally a
result of:
²adding incorrect fluid
²failure to clean dipstick and fill tube when
checking level
²engine coolant entering the fluid
²internal failure that generates debris
²overheat that generates sludge (fluid break-
down)
²failure to replace contaminated converter after
repair
The use of non-recommended fluids can result in
transmission failure. The usual results are erratic
shifts, slippage, abnormal wear and eventual failure
due to fluid breakdown and sludge formation. Avoid
this condition by using recommended fluids only.
The dipstick cap and fill tube should be wiped
clean before checking fluid level. Dirt, grease and
other foreign material on the cap and tube could fall
into the tube if not removed beforehand. Take the
time to wipe the cap and tube clean before withdraw-
ing the dipstick.
Engine coolant in the transmission fluid is gener-
ally caused by a cooler malfunction. The only remedy
is to replace the radiator as the cooler in the radiator
is not a serviceable part. If coolant has circulated
through the transmission, an overhaul is necessary.
The torque converter should be replaced whenever
a failure generates sludge and debris. This is neces-
sary because normal converter flushing procedures
will not remove all contaminants.
STANDARD PROCEDURE
CHECK OIL LEVEL
(1) Verify that the vehicle is parked on a level sur-
face.
(2) Remove locking pin (1) (Fig. 149). Remove the
plate of the locking pin with a suitable tool and press
out the pin remaining in the cap downwards.
(3) Remove cap (2).
WARNING: Risk of accident from vehicle starting off
by itself when engine running. Risk of injury from
contusions and burns if you insert your hands into
the engine when it is started or when it is running.
Secure vehicle to prevent it from moving off by
itself. Wear properly fastened and close-fitting work
clothes. Do not touch hot or rotating parts.
(4) Actuate the service brake. Start engine and let
it run at idle speed in selector lever position ªPº.
(5) Shift through the transmission modes several
times with the vehicle stationary and the engine
idling
(6) Warm up the transmission, wait at least 2 min-
utes and check the oil level with the engine running.
Push the Oil Dipstick 8863A in up to the stop on the
electrohydraulic unit and pull out again, read off oil
level, repeat if necessary.
NOTE: The dipstick will protrude from the fill tube
approximately 75mm (3 inches) when installed.
Fig. 149 Remove Dipstick Tube Cap Lock
1 - LOCKING PIN
2 - TUBE CAP
3 - DIPSTICK TUBE
21 - 132 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

HEATING & AIR CONDITIONING
TABLE OF CONTENTS
page page
HEATING & AIR CONDITIONING
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING
A/C PERFORMANCE....................3
HEATER PERFORMANCE TEST...........5
ATC FUNCTION TEST...................6
SPECIFICATIONS
HEATING-A/C SYSTEM..................6CONTROLS-FRONT........................8
CONTROLS - REAR......................24
DISTRIBUTION - FRONT...................45
DISTRIBUTION - REAR....................52
PLUMBING.............................60
CABIN HEATER.........................104
HEATING & AIR CONDITION-
ING
DESCRIPTION
An automatic temperature control (ATC) single
zone type heating-A/C system is standard equipment
on this model.
To maintain the performance level of the heating,
ventilation and air conditioning (HVAC) system, the
engine cooling system must be properly maintained.
The use of a bug screen is not recommended. Any
obstructions in front of the radiator or A/C condenser
will reduce the performance of the A/C and engine
cooling systems.
The engine cooling system includes the radiator,
thermostat, radiator hoses and the engine coolant
pump. Refer to 7 - Cooling for more information
before opening or attempting any service to the
engine cooling system.
All vehicles are equipped with a common ventila-
tion housing (Fig. 1) located in the engine compart-
ment which includes:
²Blower motor
²Blower motor resistor block
²Recirculation door and actuator
All vehicles are also equipped with a common
heater housing (Fig. 2) mounted under the instru-
ment panel which includes:
²Heater core
²Evaporator core
²Evaporator temperature sensor
²Expansion valve
²Air outlet temperature sensor
²Mode doors
Fig. 1 Ventilation Housing
1 - NUT (5)
2 - WASHER (5)
3 - VENTILATION HOUSING
4 - HOUSING COVER
VAHEATING & AIR CONDITIONING 24 - 1

When the outside air contains smoke, odors, high
humidity, or if rapid cooling is desired, interior air
can by recirculated by selecting the Recirculation
Mode with the mode control knob. The mode control
knob operates the recirculation door through use of a
vacuum actuator. When the Recirculation Mode is
selected, the recirculation door is closed to prevent
outside air from entering the passenger compart-
ment.
To maintain minimum evaporator temperature and
prevent evaporator freezing, an evaporator tempera-
ture sensor is used.
The A/C system is designed for the use of non-CFC,
R-134a refrigerant only and uses an expansion valve
to meter refrigerant flow to the evaporator.
DIAGNOSIS AND TESTING
A / C PERFORMANCE
The A/C system is designed to provide the passen-
ger compartment with low temperature and low
humidity air. The A/C evaporator, located in the
HVAC housing is cooled to temperatures near the
freezing point. As warm damp air passes over the
fins of the A/C evaporator, the air transfers its heat
to the refrigerant in the evaporator coils and the
moisture in the air condenses on the evaporator fins.
During periods of high heat and humidity, an A/C
system will be more effective in the Recirculation
mode (max-A/C). With the system in the Recircula-
tion mode, only air from the passenger compartment
passes through the A/C evaporator. As the passenger
compartment air dehumidifies, the A/C system per-
formance levels rise.
Humidity has an important bearing on the temper-
ature of the air delivered to the interior of the vehi-
cle. It is important to understand the effect that
humidity has on the performance of the A/C system.
When humidity is high, the A/C evaporator has to
perform a double duty. It must lower the air temper-
ature, and it must lower the temperature of the
moisture in the air that condenses on the evaporator
fins. Condensing the moisture in the air transfers
heat energy into the evaporator fins and coils. This
reduces the amount of heat the A/C evaporator can
absorb from the air. High humidity greatly reduces
the ability of the A/C evaporator to lower the temper-
ature of the air.
However, evaporator capacity used to reduce the
amount of moisture in the air is not wasted. Wring-
ing some of the moisture out of the air entering the
vehicle adds to the comfort of the passengers.
Although, an owner may expect too much from their
A/C system on humid days. A performance test is the
best way to determine whether the system is per-
forming up to design standards. This test also pro-
vides valuable clues as to the possible cause oftrouble with the A/C system. The ambient air tem-
perature in the location where the vehicle will be
tested must be a minimum of 21É C (70É F) for this
test.
A / C PERFORMANCE TEST
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-
tions could result in possible personal injury or
death.
NOTE: Very specific instructions and conditions
pertain to this procedure which are significantly dif-
ferent than procedures used in other vehicle appli-
cations. Follow each step in the order they are
presented. Do not skip steps or change conditions
from those stated or results will be adversely
affected and invalid.
NOTE: When connecting the service equipment
coupling to the line fitting, verify that the valve of
the coupling is fully closed. This will reduce the
amount of effort required to make the connection.
(1) Check for diagnostic trouble codes using a
DRBIIItscan tool. If no DTCs are found in the
engine control module (ECM), go to Step 2. If any
DTCs are found, repair as required, then proceed to
Step 2.
(2) Place the vehicle in the shade and operate the
heating-A/C system under the following conditions.
²Engine at idle at operating temperature
²All doors or windows open
²Transaxle in Neutral
²All A/C duct louvers open
²A/C-heater controls set to fresh air (NOT Recir-
culate), full cool, panel mode, high blower and with
A/C compressor engaged.
NOTE: The A/C compressor clutch is de-energized
under any of the following conditions:
²Restricted compressor (thermal fuse in the pul-
ley)
²Low pressure in the system
²Low evaporator temperature
²Hard acceleration (WOT)
²High coolant temperatures
(3) Insert a thermometer in the driver side center
panel air outlet and operate the A/C system until the
thermometer temperature stabilizes.
VAHEATING & AIR CONDITIONING 24 - 3