Table of Contents
Advertisement
Automatic Transmission
Symptom Troubleshooting Index (cont'd)
Symptom
The A/T does not
shift
Erratic shifting;
Fails to shift in D4;
does not upshift to
4th
Erratic shifting;
Fails to shift in D4
and D3; does not
upshift to 3rd and
4th
Erratic shifting;
Fails to shift in D4
and D3; starts off
in 3rd
Excessive shock,
or flares on all
upshifts and
downshifts
Excessive shock or
flares on 1-2
upshift or 2-1
downshift
14-14
Probable cause(s)
Modulator valve defective.
1.
Shift solenoid valve A
defective
2.
Mainshaft speed sensor
defective
3.
Countershaft speed
sensor defective
4.
Shift valve A defective
5.
Shift valve D defective
1.
Shift solenoid valve B
defective
2.
Shift fork shaft stuck
3.
Shift valve B defective
4.
Servo control valve
defective
1.
Shift solenoid valve B
defective
2.
Shift valve B defective
3.
Shift valve E defective
1.
A/T clutch pressure
control solenoid valves
A and B defective
2.
CPC valve A defective
3.
CPC valve B defective
4.
Foreign material in
separator plate orifice
1.
Shift solenoid valve C
defective
2.
2nd clutch pressure
switch or circuit defective
3.
Foreign material in
separator plate orifice
4.
Shift valve C defective
5.
1st accumulator defective
6.
2nd accumulator
defective
7.
1st check ball stuck
8.
2nd check ball stuck
9.
1st clutch defective
10.
2nd clutch defective
Check the line pressure.
•
Inspect the O-ring, and check the shift solenoid valve
for seizure.
•
Check the D4 indicator, and check for loose connectors.
Inspect the transmission range switch. If the
transmission range switch is faulty, replace it. If the
transmission range switch is out of adjustment, adjust it
and the shift cable.
•
Check the D4 indicator, and check for loose connectors.
Inspect the O-ring, and check the shift solenoid valve
for seizure.
•
Check for a missing shift fork bolt on the shift fork shaft.
Check the D4 indicator, and check for loose connectors.
Inspect the O-ring, and check the shift solenoid valve for
seizure.
•
Check the D4 indicator, and check for loose connectors.
Inspect the A/T clutch pressure control solenoid valve
body gasket and ATF feed pipes for wear and damage.
If the A/T clutch pressure control solenoid valve is stuck,
inspect the CPC valves.
•
If the ATF strainer is clogged with particles of steel or
aluminum, inspect the ATF pump. If the ATF pump is
OK and no cause for the contamination is found,
replace the torque converter.
•
Check the D4 indicator, and check for loose connectors.
Inspect the O-rings, and check the shift solenoid valve
for seizure.
•
Check the D4 indicator, and check for loose connectors.
Check that the outlet is not clogged inside of the
connector.
•
Check the 1st and 2nd clutch pressures.
•
Inspect the clutch piston and O-rings. Check the spring
retainer for wear and damage. Inspect the clutch-end-
plate-to-top-disc clearance. If the clearance is out of
tolerance, inspect the clutch discs and plates for wear
and damage. If the discs and plates are worn or
damaged, replace them as a set. If they are OK, adjust
the clutch end plate clearance.
Notes
Advertisement
Chapters
Table of Contents
Troubleshooting
