Tilt & Telescopic Manual Switch Circuit
NOTE:
If LEXUS scan tool is available, start test from step 1). If this scan tool is not available, start test from step 2.
- Connect LEXUS scan tool to Data Link Connector 3 (DLC3) located under left side of instrument panel. Turn ignition and scan tool on. Select DATA LIST mode on scan tool. Check voltage while operating tilt and telescopic manual switch. Operate manual switch in each position and note voltage reading. See TILT & TELESCOPIC MANUAL SWITCH VOLTAGE table. If all voltages are as specified, go to next test listed in SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING. If all voltages are not as specified, go to step 3. If voltage is not as specified in all directions, replace tilt and telescopic manual switch.
- If scan tool is not available, remove tilt and telescopic ECU from its mounting, leaving wiring harness connector attached. Turn ignition on. Using a voltmeter, measure voltage by backprobing rear of terminal No. 8 (Red/Yellow wire) with voltmeter positive lead at 22-pin ECU harness connector T9 and by backprobing rear of terminal No. 3 (White/Black wire) with negative lead at 12-pin ECU harness connector T8. See Figure. Operate manual switch in each position and note voltage reading. See TILT & TELESCOPIC MANUAL SWITCH VOLTAGE table. If all voltages are as specified, go to next test listed in SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING. If all voltages are not as specified, go to next step. If voltage is not as specified in all directions, replace tilt and telescopic manual switch.TILT & TELESCOPIC MANUAL SWITCH VOLTAGE
Switch Position Voltage Neutral 0-.20 Telescopic Extend 2.05-2.75 Telescopic Retract .65-.95 Tilt Down .30-.50 Tilt Up 1.30-1.70 - Turn ignition off. Remove tilt and telescopic ECU, leaving wiring harness connector attached. Turn ignition on. Using a voltmeter, measure voltage between ground and by backprobing rear of terminal No. 20 (Blue wire) with voltmeter positive lead at 22-pin ECU harness connector T9. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, go to step 5.
- Turn ignition off. Disconnect 10-pin tilt and telescopic manual switch harness connector. Using an ohmmeter, measure resistance between terminals No. 4 (Red/Yellow wire) and No. 9 (Blue wire) at 10-pin manual switch harness connector. See Fig 1. Operate manual switch in each position and note resistance. See TILT & TELESCOPIC MANUAL SWITCH RESISTANCE table. If resistances are as specified, go to next step. If resistances are not as specified, replace tilt and telescopic manual switch.TILT & TELESCOPIC MANUAL SWITCH RESISTANCE
Switch Position Ohms Telescopic Extend 160 Telescopic Retract 790 Tilt Down 1,990 Tilt Up 360 - Check wiring harness and connectors between tilt and telescopic ECU and manual switch. See WIRING DIAGRAMS . Repair or replace as necessary. If wiring harness and connectors are okay, go to next test listed in SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING.