CHRYSLER VOYAGER 1996 Service Manual

Diagnosis Guide
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Diagnosis Guide
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Diagnosis Guide
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Diagnosis Guide
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Diagnosis Guide
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Diagnosis Guide
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may not be detected. Practically any condition can be
caused by leaking hydraulic circuits or sticking
valves.
Therefore, unless the condition is obvious, the tran-
saxle should never be disassembled until hydraulic
pressure tests have been performed.
HYDRAULIC PRESSURE TESTS
Pressure testing is a very important step in the
diagnostic procedure. These tests usually reveal the
cause of most transaxle problems.
Before performing pressure tests, be certain that
fluid level and condition, and control cable adjust-
ments have been checked and approved. Fluid must
be at operating temperature (150 to 200 degrees F.).
Install an engine tachometer, raise vehicle on hoist
which allows front wheels to turn, and position
tachometer so it can be read.
Disconnect throttle cable and shift cable from tran-
saxle levers so they can be controlled from outside
the vehicle.
Attach 150 psi gauges to ports required for test
being conducted. A 300 psi gauge (C-3293) is required
for reverse pressure test at rear servo.
Test port locations are shown in (Fig. 2) .
TEST ONE (SELECTOR IN 1)
(1) Attach gauges to line and low-reverse ports.
(2) Operate engine at 1000 rpm for test.
(3) Move selector lever on transaxle all the way
rearward (1 position).
(4) Read pressures on both gauges as throttle lever
on transaxle is moved from full clockwise position to
full counterclockwise position.
(5) Line pressure should read 52 to 58 psi with
throttle lever clockwise. Pressure should gradually
increase, as lever is moved counterclockwise, to 80 to
88 psi.(6) Low-reverse pressure should read the same as
line pressure within 3 psi.
(7) This tests pump output, pressure regulation,
and condition of rear clutch and rear servo hydraulic
circuits.
TEST TWO (SELECTOR IN 2)
(1) Attach one gauge to line pressure port and tee
another gauge into lower cooler line fitting. This will
allow lubrication pressure readings to be taken..
(2) Operate engine at 1000 rpm for test.
(3) Move selector lever on transaxle one detent for-
ward from full rearward position. This is selector 2
position.
(4) Read pressures on both gauges as throttle lever
on transaxle is moved from full clockwise position to
full counterclockwise position.
(5) Line pressure should read 52 to 58 psi with
throttle lever clockwise. Pressure should gradually
increase, as lever is moved counterclockwise, to 80 to
88 psi.
(6) Lubrication pressure should be 10 to 25 psi
with lever clockwise and 10 to 35 psi with lever full
counterclockwise.
(7) This tests pump output, pressure regulation,
and condition of rear clutch and lubrication hydraulic
circuits.
TEST THREE (SELECTOR IN D)
(1) Attach gauges to line and kickdown release
ports.
(2) Operate engine at 1600 rpm for test.
(3) Move selector lever on transaxle two detents
forward from full rearward position. This is selector
D position.
(4) Read pressures on both gauges as throttle lever
on transaxle is moved from full clockwise position to
full counterclockwise position.
(5) Line pressure should read 52 to 58 psi with
throttle lever clockwise. Pressure should gradually
ELEMENTS IN USE AT EACH POSITION OF THE SELECTOR LEVER
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DIAGNOSIS AND TESTING (Continued)

increase, as lever is moved counterclockwise to 80 to
88 psi.
(6) Kickdown release is pressurized only in direct
drive and should be same as line pressure within 3
psi, up to kickdown point.
(7) This tests pump output, pressure regulation,
and condition of rear clutch, front clutch, and
hydraulic circuits.
TEST FOUR (SELECTOR IN REVERSE)
(1) Attach 300 psi gauge to low-reverse port.
(2) Operate engine at 1600 rpm for test.
(3) Move selector lever on transaxle four detents
forward from full rearward position. This is selector
R position.
(4) Low-reverse pressure should read 180 to 220
psi with throttle lever clockwise. Pressure should
gradually increase, as lever is moved counterclock-
wise to 260 to 300 psi.
(5) This tests pump output, pressure regulation,
and condition of front clutch and rear servo hydraulic
circuits.
(6) Move selector lever on transaxle to D position
to check that low-reverse pressure drops to zero.
(7) This tests for leakage into rear servo, due to
case porosity, which can cause reverse band burn out.
TEST RESULT INDICATIONS
(1) If proper line pressure, minimum to maximum,
is found in any one test, the pump and pressure reg-
ulator are working properly.
(2) Low pressure in D, 1, and 2 but correct pres-
sure in R indicates rear clutch circuit leakage.
(3) Low pressure in D and R but correct pressure
in 1 indicates front clutch circuit leakage.
Fig. 2 Test Port Locations
Fig. 3 Governor Pressure Tap
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(4) Low pressure in R and 1 but correct pressure
in 2 indicates rear servo circuit leakage.
(5) Low line pressure in all positions indicates a
defective pump, a clogged filter, or a stuck pressure
regulator valve.
GOVERNOR PRESSURE
Test only if transaxle shifts at wrong vehicle
speeds when throttle cable is correctly adjusted.
(1) Connect a 0-150 psi pressure gauge to governor
pressure take-off point. It is located at lower right
side of case, below differential cover.
(2) Operate transaxle in third gear to read pres-
sures. The governor pressure should respond
smoothly to changes in mph and should return to 0
to 3 psi when vehicle is stopped. High pressure at
standstill (above 3 psi) will prevent the transaxle
from downshifting.
THROTTLE PRESSURE
No gauge port is provided for throttle pressure.
Incorrect throttle pressure should be suspected if
part throttle upshift speeds are either delayed or
occur too early in relation to vehicle speeds. Engine
runaway on shifts can also be an indicator of low
throttle pressure setting, or misadjusted throttle
cable.
In no case should throttle pressure be adjusted
until the transaxle throttle cable adjustment has
been verified to be correct.
CLUTCH AND SERVO AIR PRESSURE TESTS
A no drive condition might exist even with correct
fluid pressure, because of inoperative clutches or
bands. The inoperative units, clutches, bands, and
servos can be located through a series of tests. This
is done by substituting air pressure for fluid pressure
(Fig. 4) .
The front and rear clutches, kickdown servo, and
low-reverse servo may be tested by applying air pres-
sure to their respective passages. To make air pres-
sure tests, proceed as follows:
NOTE: Compressed air supply must be free of all
dirt or moisture. Use a pressure of 30 psi.
Remove oil pan and valve body. Refer to Valve
Body for removal procedure.
FRONT CLUTCH
Apply air pressure to front clutch apply passage
and listen for a dull thud which indicates that front
clutch is operating. Hold air pressure on for a few
seconds and inspect system for excessive oil leaks.
REAR CLUTCH
Apply air pressure to rear clutch apply passage
and listen for a dull thud which indicates that rear
clutch is operating. Also inspect for excessive oil
leaks. If a dull thud cannot be heard in the clutches,
place finger tips on clutch housing and again apply
air pressure. Movement of piston can be felt as the
clutch is applied.
KICKDOWN SERVO (FRONT)
Direct air pressure into KICKDOWN SERVO ON
passage. Operation of servo is indicated by a tighten-
ing of front band. Spring tension on servo piston
should release the band.
LOW AND REVERSE SERVO (REAR)
Direct air pressure into LOW-REVERSE SERVO
APPLY passage. Operation of servo is indicated by a
tightening of rear band. Spring tension on servo pis-
ton should release the band.
If clutches and servos operate properly, no upshift
indicates that a malfunction exists in the valve body.
FLUID LEAKAGE-TRANSAXLE TORQUE
CONVERTER HOUSING AREA
(1) Check for source of leakage.
(2) Since fluid leakage near the torque converter
area may be from an engine oil leak, the area should
be checked closely. Factory fill fluid is dyed red and,
therefore, can be distinguished from engine oil.
(3) Prior to removing the transaxle, perform the
following checks:
(4) When leakage is determined to originate from
the transaxle, check fluid level prior to removal of
the transaxle and torque converter.
(5) High oil level can result in oil leakage out the
vent in the dipstick. If the fluid level is high, adjust
to proper level.
(6) After performing this operation, inspect for
leakage. If a leak persists, perform the following
operation on the vehicle. This will determine if the
torque converter or transaxle is leaking.
TORQUE CONVERTER LEAKAGE
Possible sources of torque converter leakage are:
²Torque converter weld leaks at the outside diam-
eter (peripheral) weld.
²Torque converter hub weld.
²Torque converter impeller shell cracked adjacent
to hub.
²At drive lug welds.
NOTE: Hub weld is inside and not visible. Do not
attempt to repair. Replace torque converter.
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SERVICE PROCEDURES
FLUID AND FILTER CHANGE
When the factory fill fluid is changed, only fluids
labeled MOPARtATF PLUS 3 (Automatic Transmis-
sion fluid) Type 7176 should be used.
If the transaxle is disassembled for any reason, the
fluid and filter should be changed.
30,000 MILE TRANSAXLE OIL CHANGE
When a vehicle attains 30,000 miles on its odome-
ter it is recommended that the transaxle oil be
changed. To change the oil, use the procedure that
follows:
It is recommended that a transaxle fluid exchanger
(ATF 2000+ or equivalent) be used to replace the
used fluid in the transaxle. If a fluid exchanger is not
available use a fluid suction pump (Vaculayor equiv-
alent) to draw the fluid out of the dipstick tube. If a
fluid suction pump is not available remove the oil
pan and drain the fluid.
CAUTION: Chrysler Corporation does not recom-
mend using any fluid exchanger that introduces
additives into the transaxle.TRANSAXLE FLUID EXCHANGER METHOD
(1) To perform the transaxle fluid exchange, the
transaxle must be at operating temperature. Drive
the vehicle till it reaches full operating temperature.
(2) Verify that the fill tank on the transaxle fluid
exchanger (ATF 2000+ or equivalent) is clean and
dry.
(3) Fill the tank to the recommended fill capacity
with Mopar ATF Plus 3 Type 7176.
(4) Hookup the vehicle to the machine following
the manufacturers instructions. Perform the
exchange procedure following the instructions pro-
vided with the machine.
(5) Once machine has completed the fluid
exchange. Check the fluid level and condition and fill
to proper level with Mopar ATF Plus 3 Type 7176.
NOTE: Verify that the transaxle cooler lines are
tightened to proper specifications. Cooler line
torque specification is 2 N²m (18 in. lbs.).
DIPSTICK TUBE FLUID SUCTION METHOD
(1) When performing the fluid suction method,
make sure the transaxle is at full operating temper-
ature.
Fig. 4 Air Pressure Tests
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