Isuzu 1999 RODEO Workshop Manual page 1796

7A–14 AUTOMATIC TRANSMISSION (4L30–E)
Chart 2: No Forward Gears In Any Range/No Reverse
Step
1 Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
2 1. Check internal linkage:
– Manual linkage (58) not moving manual valve (326).
2. Check for internal mechanical damage:
– Turbine shaft (506) broken loose.
– Overrun roller clutch (576) broken loose.
Was the problem found?
Chart 3: No Engine Brake In Any Range
Step
1 Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
2 1. Check for overrun clutch leaks caused by:
– Damaged piston lip (513)
– Check ball defective (504)
2. Check for overrun lockout valve (705) stuck by foreign
material.
3. Check for leaks at turbine shaft (506) caused by:
– Teflon seal rings damaged (508)
– Excessive wear of turbine shaft bearing surfaces.
Was the problem found?
Action
Action
Yes
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
Go to Step 2
Repair or replace
Yes
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
Go to Step 2
Repair or replace
No
section.
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No
section.
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