Throttle Position Sensor (TPS) Adjustment Procedure

IMPORTANT:
This adjustment procedure must be made with the TPS installed on the engine of the vehicle. Incorrect adjustment of this sensor may cause one or more of the following DTC's to be displayed: P1447, P0120, P0510, P0731, P0732, P0733, P0734, P1705.

1. Check fast idle cam (FIC) function, if equipped (refer to appropriate Service Manual). When done, make sure the engine is at normal operating temperature and the fast idle cam (if equipped) has released. Then turn the engine off.





2. Raise the throttle opener rod OFF of the throttle drum as follows (refer to Figure 5):

a. Remove the vacuum hose connected to the throttle opener.

b. Connect a suitable vacuum hose to a hand-operated vacuum pump and the opener.

c. Apply vacuum of more than -11.81 inHg (-300 mmHg) until the throttle drum becomes free from the rod of the throttle opener.





3. Disconnect the harness connector (see Figure 6) from the closed throttle position switch portion of the throttle position sensor (TPS).





4. Connect an ohm meter across the terminals for the closed throttle position switch (see Figure 7). There should be continuity across the terminals with the throttle closed.

NOTE:
Do not touch the throttle drum when checking the closed throttle position switch signal or continuity. Doing so may cause an incorrect adjustment.





5. Insert a 0.3 mm (0.012 in.) feeler gauge between the throttle adjustment screw and the throttle drum stop (see Figure 8a). The closed throttle position switch should still have continuity.

CAUTION:
Never adjust the Throttle Adjustment Screw (TAS). It is pre-set at the factory.

6. Insert a 0.4 mm (0.016 in.) feeler gauge between the throttle adjustment screw and the throttle drum stop (see Figure 8b). The closed throttle position switch should NOT have continuity.

7. If the results of steps 5 and/or 6 are N/G, loosen the TPS retaining bolts and adjust the switch to achieve the correct results.

8. Tighten the TPS retaining bolts, then repeat steps 5 and 6 to ensure the TPS adjustment is still within specification.

9. Reconnect the harness connector to the closed throttle position switch portion of the throttle position sensor (TPS).

10. Release the vacuum and disconnect the vacuum pump hose from the throttle opener.

11. Reinstall the original vacuum hose securely to the throttle opener.

Reset throttle position sensor idle position memory.

NOTE:
Failure to reset the TPS idle position memory may result in the idle speed staying higher than specification.

12. Start engine and warm it to operating temperature.

NOTE:
Always warm up engine to normal operation temperature. If the engine is cool, the throttle position memory will not be reset correctly.

13. Using CONSULT select ENGINE, DATA MONITOR (Manual trigger), Selections From Menu, CLSD THL/P SW (for 1997-98 JR50) or CLSD THL P0S (for 1999 JR5O), and Enter.

14. Stop engine (turn ignition switch "OFF").

15. Turn ignition switch "ON" and wait at least five seconds.

16. Turn ignition switch "OFF" and wait at least ten seconds.

17. Repeat steps 15 and 16 for 1 to 16 times until CLSD THL/P SW (for 1997-98 JR50) or CLSD THL POS (for 1999 JR5O) in CONSULT changes to "ON".