ZF Automatic Transmissions Service Manual
1.3 FAULT DIAGNOSIS
The followina tables are intended as a auide to diaanosis of Dossible faults in the ZF 4 HP 22 transmission. When the
fault involvesa leak, it is recommendedthat it is located by the use of a crack detection fluid, eg Met-L-Check, which
is available in spray form and permits the leak to be located after a short test drive.
1.3.1 Initial Checks
Note: Before attempting diagnosis, ensure that the following settings are checked:
Transmission oil level.
. Ensure that the transmission is at normal operating temperature, eg by conducting a road test. If starting from cold,
. Check that the vehicle is on level ground.
. Firmly apply the parking and footbrakes and run the engine at idle speed.
. To ensure that the system is primed, slowly move the selector lever through all the gear positions.
. With the engine still running, engage ‘P‘ Park, withdraw the dipstick and wipe with a lint free cloth.
. Replace the dipstick slowly and withdraw it noting the level.
. Top up as required and recheck the level.
check
for presence of oil on dipstick at idle
in Park before start of road test.
1.3.2 Engine Tune
Selector cable adjustment.
Check gear selection in all selector positions.
If in doubt, select ’N’, disconnect the cable at the gearbox selector lever, check that the gearbox lever is in ’N’ position
. Adjust as necessary, see Vehicle Service Manual.
(third
detent from the rear) and refit the selector cable ball pin to the lever.
Kickdown switch adjustment, see Vehicle Service Manual.
1.3.3 Stall Test
. Ensure the transmission is at normal running temperature.
. Fully apply the parking brake.
. Fully depress the footbrake.
= Select position ‘D‘- Drive.
. Fully depress the accelerator(’kick-down’ detent fully depressed).
. Note the tachometer reading.
Start
the engine.
. Compare the tachometer reading to the specification.
CAUTION: This test must not last more than 5 seconds. Always allow the engine to idle for at least 2 minutes be- tween tests to allow the transmission fluid to cool down. Do not carry out more than three tests in any
half-hour.
1.3.4 Road Test
Fully check all shift speeds and note. Compare the results with the specification in addition to general observations
of transmission behaviour, noises, leaks etc., and consult the following Fault Finding Chart.
CAUTION: When renewing the transmission, ALWAYS flush out the oil cooler and feed and return pipes.
1.3.5 Electrical Checks
If any electrical component fault issuspected, referto the Electrical Diagnostic Manual (EDM) to verify the failure mode
before a repair or replacement is attempted.
Issue 1 August 1994 33
ZF Automatic Transmissions Service Manual
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2.3 FAULT DIAGNOSIS
The following tables are intended as a guide to diagnosis of possible faults in the ZF 4 HP 24 E transmission. When
the fault involves a leak,
it is recommended that it is located by the use of a crack detection fluid, eg. Met-L-Check,
which is available in spray form and permits the leak to be located after a short test drive.
2.3.1 Initial Checks
&@: Before attempting fault diagnosis, ensure that the following settings are checked:
Transmission oil level
. Ensure that the transmission is at normal operating temperature, e.g. by conducting a 20 mile road test. If starting
. Check that the vehicle is on level ground.
. Firmly apply the parking and footbrakes and run the engine at idle speed.
. To ensure that the system is primed, slowly move the selector lever through all the gear positions.
. With the engine still running, engage 'P' Park, withdraw the dipstick and wipe with a lint free cloth.
. Replace the dipstick slowly and withdraw it noting the level.
. Top up as required and recheck the level.
from
cold: check for presence of
oil on dipstick at idle in 'P' Park before setting off.
Note: The oil level can only be accuratelychecked when at normal temperature-approximately 20 miles at moderate
speeds.
2.3.2 Engine Tune
Selector cable adjustment
. Check gear selection in all selector positions.
. If in doubt, select 'N', disconnect the cable at the gearbox selector lever, checkthat the gearbox lever is in 'N' position
. Adjust as necessary at the selector lever inside the vehicle.
(third detent from the rear) and refit the selector cable ball pin to the lever.
2.3.3 Stall Test
. Ensure the transmission is at normal running temperature.
. Fully apply the parking brake.
. Start the engine.
= Fully depress the footbrake.
. Select position 'D'- Drive.
. Fully depress the accelerator('kick-down' switch fully depressed).
. Note the tachometer reading.
. Compare the tachometer reading to the specification.
CAUTION: This test must not last more than 5 seconds. Always allow the engine to idle for at least 2 minutes between
tests to allow the transmission fluid to cool down. Do not carry out more than three tests in any half-hour.
Jaguar Diagnostic Equipment
(JDE) must be interrogated and any faults identified and rectified (see JDS Manual / In- structions). Check mode switch and gear selector positions using JDE.
60 Issue 1 August 1994
