Jeep Cherokee 2000, Руководство по обслуживанию, Страница: 1150 / 1528

(6) Shift transmission into D range and note line
pressure with engine at curb idle speed. Pressure
should be 61–to–70 psi (421–to–481 kPa).
(7) Press accelerator pedal to wide open throttle
position and note line pressure. Pressure should be
173–to–209 psi (1196–to–1442 kPa).
CAUTION: Do not hold wide open throttle for more
than 3–4 seconds at a time.
(8) Shift transmission into Reverse and note line
pressure with engine at curb idle speed. Pressure
should be 75–to–90 psi (519–to–618 kPa).
(9) Press accelerator to wide open throttle position
and note line pressure in Reverse. Pressure should
be 213–to–263 psi (1471–to–1814 kPa).
CAUTION: Do not hold wide open throttle for more
than 4 seconds.
(10) If line pressure is not within specifications,
adjust transmission throttle cable and repeat pres-
sure test.
PRESSURE TEST ANALYSIS
If pressures in D and Reverse are higher than
specified in test, check for the following:
•
throttle cable loose, worn, binding or out of
adjustment
•
throttle valve, downshift plug, throttle cam, or
primary regulator valve are sticking, worn or dam-
aged
If pressures in D and Reverse are lower than spec-
ified in test, check for following:
•
throttle cable loose, worn, binding or out of
adjustment
•
throttle valve, downshift plug, or throttle cam
sticking, worn or damaged
•
primary regulator valve sticking, worn, or dam-
aged
•
oil pump gears or housing worn, or damaged
•
overdrive clutch worn, or damaged
If pressures are low in D range only, check for fol-
lowing:
•
forward clutch worn or damaged
•
fluid leakage in D range circuit (component seal
and O–rings)
If pressures are low in Reverse only, check for fol-
lowing:
•
shift cable and manual valve out of adjustment
•
fluid leakage in reverse circuit (component seal
and O–rings)
•
direct clutch worn or damaged
•
first/reverse brake worn or damaged
TIME LAG TEST
This test checks general condition of the overdrive
clutch, forward clutch, rear clutch and first/reverse
brake. Condition is indicated by the amount of time
required
for clutch/brake engagement with the
engine at curb idle speed. Engagement time is mea-
sured for D and Reverse positions. A stop watch is
recommended for test accuracy.
TEST PROCEDURE
(1) Check and adjust transmission fluid level if
necessary.
(2) Bring transmission to normal operating tem-
perature.
(3) Apply parking brakes and turn off air condi-
tioning unit.
(4) Shift transfer case into 2H range.
(5) Start engine and check curb idle speed. Adjust
speed if necessary. Curb idle must be correct to
ensure accurate test results.
(6) Shift transmission into Neutral and set stop
watch.
(7) During following test steps, start stop watch as
soon as shift lever reaches D and Reverse ranges.
(8) Shift transmission into D range and record
time it takes for engagement. Repeat test two more
times.
(9) Reset stop watch and shift transmission back
to Neutral.
(10) Shift transmission into Reverse and record
time it takes for engagement. Repeat test two more
times.
Fig. 39 Pressure Test Gauge Connection
1 – PRESSURE GAUGE
2 – TEST PORT
21 - 242 AW–4 AUTOMATIC TRANSMISSION
XJ
DIAGNOSIS AND TESTING (Continued)