Vacuum Operated Components - 4WD Indicator Faults

VACUUM PIPING





1. Pull out the Hose A in figure and install a vacuum gauge.
2. Plug up Hose B in figure to prevent the leak of vacuum.
3. Start the engine and measure vacuum 2 or 3 minutes afterward.
4. Repeat 1) and 2) but with Hose A plugged and Hose B pulled out.
5. If vacuum measures -400mmHg, or if it shows a sudden drop immediately after engine stop, inspect the hose, tank, and pipe for damage.

NOTE: Be careful not to permit the entry of dust and water during inspection.

6. Pull out Hose D in above illustration.
7. Plug Hose E in above illustration.
8. Make sure that Hose D in above illustration is under atmospheric pressure.
9. Pull out Hose E and plug Hose D, and make sure that Hose E is under atmospheric pressure.
10. If Check 8) or 9) has revealed stoppage, check and see that there is no bend, foreign matter in the hose or in the filter. If there is trouble, repair or replace.

CHECK VALVE





1. Apply vacuum from the orange colored side (l).

Vacuum: -400mmHg

2. Check leakage of vacuum.
3. Make sure that vacuum cannot be applied from the black colored side(2).
4. If vacuum is not applicable as much as -400mmHg, and if there is resistance on the intake side, replace with a new check valve.

VSV ASSEMBLY





Inspect the vehicle side harness as follows:
1. Remove connector.
2. Shift transfer lever to 2H and start the engine.

NOTE: Do not move the vehicle while inspection.

3. Make sure that there is continuity in the vehicle side of harness. If there is no continuity, check transfer shift switch and wiring.
Inspect both VSVs as follows:
1. With battery not connected (Usual).





A - C: There is continuity
B: Closed

2. With battery connected
A - B: There is continuity
C: Closed

3. If 1) and 2) fail, replace with a new VSV.

AXLE POSITION SWITCH





1. With ball (1) being free

A - B: There is continuity

2. With ball forced into the switch

A - B: No continuity

3. If 1) and 2) fail, replace with a new switch.

MOTOR ACTUATOR ASSEMBLY
Inspect the function of the motor actuator assembly as follows:





1. Disassemble the motor actuator from transfer rear case.
2. Connect the terminals as shown in figure.





Shift rod of the motor actuator moves and stops at 4WD position.





3. Connect the terminals as shown in figure.
Shift rod of the motor actuator moves and stops at 2WD position.

4. If 2) and 3) fail, replace with a new motor actuator.

TRANSFER POSITION SWITCH





1. With ball being free.

A - B: There is continuity.

2. With ball forced into the switch.

A - B: No continuity.

3. If 1) and 2) fail, replace with a new switch.