Test 54A - O/D Off Switch Circuit Or Loss Of 4TH Gear

NOTE: Perform TEST 2A before proceeding with this test. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see WIRING DIAGRAMS . Perform VERIFICATION TEST VER-1A after each repair.

CAUTION: Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.

All DTCs must be repaired before proceeding. Turn ignition on. Using scan tool, monitor O/D Off switch output. Operate O/D Off switch. If scan tool displays 4TH ALLOWED and THREE SPEED, go to step 5). If scan tool does not display 4TH ALLOWED and THREE SPEED, go to next step.
Disconnect O/D Off switch connector at bottom of shift lever. Connect and disconnect (2 to 3 times) jumper wire between connector terminals No. 3 and 4. monitor O/D Off switch output. If scan tool displays 4TH ALLOWED and THREE SPEED, replace O/D Off switch. If scan tool does not display 4TH ALLOWED and THREE SPEED, go to next step.
Use scan tool in voltmeter mode. Measure voltage at terminal No. 3 on O/D Off connector. If voltage is 10 volts or less, repair open fused ignition switch output circuit. If voltage is more than 10 volts, go to next step.
Turn ignition off. Connect O/D Off switch connector. Disconnect TCM connector. Turn ignition on. Use scan tool in voltmeter mode. Measure voltage at terminal No. 9 on TCM connector. If voltage is more than 10 volts, replace TCM. If voltage is 10 volts or less, repair open O/D Off switch sense circuit.
Ensure O/D Off switch is depressed. Using scan tool, monitor O/D Off switch input. Wiggle wires at switch connector and TCM connector. If scan tool display changes from 4TH ALLOWED to THREE SPEED, inspect and repair applicable circuits. If scan tool display does not change, system is currently operating correctly.