Cherokee 2WD L4-150 2.5L VIN H TBI (1988)
Throttle Position Sensor: Adjustments
Automatic Transmission
***UPDATED BY TSB #18-54-88
NOTE: The TPS for the fuel injection system is integral with the TPS for the automatic transmission. Therefore, adjusting the TPS correctly for the
transmission will automatically adjust the fuel injection TPS properly. The preferred method for adjusting the transmission TPS is using the MS 1700
tester in the "AUTO TRANS TEST" mode and following the instructions that the tester displays. However, the TPS can also be adjusted using a
voltmeter and the following procedure.
1.
Turn the ignition switch to the "ON" position.
Throttle Position Connector
2.
There are two wire harness connectors attached to the TPS. Input/output voltage is checked at the SQUARE, FOUR TERMINAL connector. The
terminals are identified by the letters A, B, C and D molded into the connector.
3.
Do not unplug the connector. The voltmeter leads must be inserted through the back of the connector to make contact with the terminals. Connect
the positive lead to terminal A and the negative lead to terminal D.
4.
With the throttle plate in the wide open throttle (W.O.T.) position, note the "input" voltage. It should be approximately 5.0 volts.
5.
Remove the voltmeter positive lead from terminal A and connect it to terminal B. The "output" voltage should be 0.2 volts (4% of input voltage).
If this is not the case, continue with this procedure.
6.
Adjust output voltage as follows:
a.
With the voltmeter leads still attached, carefully loosen the sensor mounting screws.
b.
Slowly rotate the sensor until the output reading is 0.2 volts with the throttle wide open.
c.
Tighten the sensor mounting screws securely. Be sure not to distrurb the sensor's position while tightening the screws.
