1996 CHRYSLER VOYAGER 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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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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