Steering Column - Power Tilt: Other Lexus GS II

Both Tilt & Telescopic Functions Do Not Work, Stops Part Way Or Does Not Stop

Check the following in order

1. TILT & TELESCOPIC ECU POWER SUPPLY CIRCUIT in SYSTEM TESTS
2. KEY UNLOCK WARNING SWITCH CIRCUIT in DIAGNOSTIC TESTS
3. BODY ECU. See PIN VOLTAGE TESTS in BODY CONTROL SYSTEMS article.
4. ACTUATOR POWER SUPPLY CIRCUIT in SYSTEM TESTS
5. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS

Only Tilt Function Does Not Work, Stops Part Way Or Does Not Stop

Check the following in order

1. TILT MOTOR CIRCUIT in SYSTEM TESTS
2. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS

Only Telescopic Function Does Not Work, Stops Part Way Or Does Not Stop

Check the following in order

1. TELESCOPIC MOTOR CIRCUIT in SYSTEM TESTS
2. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS

Both Tilt & Telescopic Functions Do Not Work

Check the following in order

1. MANUAL SWITCH CIRCUIT in SYSTEM TESTS
2. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS Only Tilt Function Does Not Work Check the following in order
3. MANUAL SWITCH CIRCUIT in SYSTEM TESTS
4. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS Only Telescopic Function Does Not Work Check the following in order
5. MANUAL SWITCH CIRCUIT in SYSTEM TESTS
6. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS

Automatic Away & Return Does Not Work

Check the following in order

1. Check automatic return function using Lexus Hand-Held Tester scan tool)
2. IGNITION SWITCH CIRCUIT in SYSTEM TESTS
3. KEY UNLOCK WARNING SWITCH CIRCUIT in DIAGNOSTIC TESTS
4. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS

Automatic Away Only Does Not Work

Check the following in order

1. KEY UNLOCK WARNING SWITCH CIRCUIT in DIAGNOSTIC TESTS
2. IGNITION SWITCH CIRCUIT in SYSTEM TESTS
3. TILT & TELESCOPIC ECU PIN VOLTAGE TESTS

ACTUATOR POWER SUPPLY CIRCUIT

1. Remove tilt and telescopic ECU with harness connectors connected. With ignition off, measure voltage between 10-pin ECU connector terminal No. 10 (Blue wire) and No. 4 (White/Black wire). (Scheme 7) If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to TROUBLE SHOOTING and identify next circuit to be checked.
2. Measure resistance between 10-pin ECU connector terminal No. 4 and ground. If resistance is less than one ohm, go to next step. If resistance is not less than one ohm, repair open White/Black wire between ECU connector and ground at left kick panel. See WIRING DIAGRAMS.
3. Check continuity of P/SEAT (30-amp) fusible link. If continuity does not exist, check and repair short to ground in Blue wire between fusible link and all components connected to fusible link. See WIRING DIAGRAMS. If continuity does not exist, check for open Blue wire between ECU connector and fusible link.

Scheme 7

IGNITION SWITCH CIRCUIT

Check voltage (backprobe) 8-pin ignition switch harness connector with ignition switch in specified position. See IGNITION SWITCH VOLTAGE table. If voltage is not as specified, repair as necessary. See appropriate POWER DISTRIBUTION article in WIRING DIAGRAMS.

IGNITION SWITCH VOLTAGE

MANUAL SWITCH CIRCUIT

1. Connect Lexus Hand-Held Tester (scan tool) to Data Link Connector 3 (DLC3). Turn ignition and scan tool on. Select DATALIST mode on scan tool. Check voltage while operating manual switch. If scan tool is not available, remove tilt and telescopic ECU with harness connector connected. Turn ignition on. Measure voltage between 10-pin ECU connector terminal No. 8 (Yellow wire) and No. 1 (White/Black wire). (Scheme 7)
2. Operate manual switch in each position and note voltage reading. See MANUAL SWITCH VOLTAGE table. If all voltages are as specified, go to TROUBLE SHOOTING and identify next circuit to be checked. If all voltages are not as specified, go to next step. If voltage in only certain directions is not as specified, replace switch. MANUAL SWITCH VOLTAGE Switch Position Voltage Telescopic Extend 2.05-2.75 Tilt Up 1.30-1.70 Telescopic Retract.65-.95 Tilt Down.30-.50
3. Remove tilt and telescopic ECU with harness connector connected, if not done in step 1). Turn ignition on. Measure voltage between 10-pin ECU connector terminal No. 3 (Yellow/Red wire) and ground. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, go step 5).
4. Disconnect 10-pin manual switch wiring harness connector. Measure resistance between manual switch connector terminals No. 4 and 9. (Scheme 8) Operate manual switch in each position and note resistance. See 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.
5. Check and repair wiring harness between tilt and telescopic ECU and manual switch. See WIRING DIAGRAMS. If wiring harness is okay, go to TROUBLE SHOOTING and identify next circuit to be checked.

MANUAL SWITCH RESISTANCE

Scheme 8

TILT & TELESCOPIC ECU POWER SUPPLY CIRCUIT

1. Remove tilt and telescopic ECU with harness connector connected. With ignition off, measure voltage between 10-pin ECU connector terminal No. 5 (Green/White wire) and No. 1 (White/Black wire). (Scheme 7) If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to TROUBLE SHOOTING and identify next circuit to be checked.
2. Measure resistance between 10-pin ECU connector terminal No. 1 and ground. If resistance is less than one ohm, go to next step. If resistance is not less than one ohm, repair open White/Black wire between ECU connector and ground at left kick panel. See WIRING DIAGRAMS.
3. Check MPX-B (10-amp) fuse. If fuse is okay, check for open Green/White wire between 10-pin ECU harness connector terminal No. 5 and fuse block. See WIRING DIAGRAMS. If fuse is faulty, check and repair short to ground in Green/White wire between tilt and telescopic ECU and fuse block.

TILT MOTOR CIRCUIT

Note. If scan tool is not available, start at step 2).

1. Connect Lexus Hand-Held Tester (scan tool) to Data Link Connector 3 (DLC3). Turn ignition and scan tool on. Select ACTIVE TEST mode on scan tool. Using scan tool, tilt steering wheel up and down. If steering wheel does not move, go to next step. If steering wheel moves, go to TROUBLE SHOOTING and identify next circuit to be checked.
2. Disconnect tilt motor connector. Connect a fused jumper wire between battery positive terminal and tilt motor connector terminal No. 3. See WIRING DIAGRAMS. Connect a jumper wire between negative battery terminal and tilt motor connector terminal No. 4.
3. Tilt motor should move column downward. Reverse polarity of jumper wires and ensure column moves upward. If operation is as specified, go to next step. If operation is not as specified, replace tilt motor and recheck system.
4. Check wiring harness between tilt motor and tilt and telescopic ECU. Repair as necessary. If wiring is okay, go to TROUBLE SHOOTING and identify next circuit to be checked.

TELESCOPIC MOTOR CIRCUIT

Note. If scan tool is not available, start at step 2).

1. Connect Lexus Hand-Held Tester (scan tool) to Data Link Connector 3 (DLC3). Turn ignition and scan tool on. Select ACTIVE TEST mode on scan tool. Using scan tool, telescope steering wheel in and out. If steering wheel does not move, go to next step. If steering wheel moves, go to TROUBLE SHOOTING and identify next circuit to be checked.
2. Disconnect telescopic motor connector. Connect a fused jumper wire between battery positive terminal and telescopic motor connector terminal No. 6. See WIRING DIAGRAMS. Connect a jumper wire between negative battery terminal and telescopic motor connector terminal No. 5.
3. Telescopic motor should move column downward. Reverse polarity of jumper wires and ensure column moves upward. If operation is as specified, go to next step. If operation is not as specified, replace telescopic motor and recheck system.
4. Check wiring harness between telescopic motor and tilt and telescopic ECU. Repair as necessary. If wiring is okay, go to TROUBLE SHOOTING and identify next circuit to be checked.

TILT & TELESCOPIC ELECTRONIC CONTROL MODULE (ECU)

Check tilt and telescopic ECU pin voltages. See TILT & TELESCOPIC ECU PIN VOLTAGE table. (Scheme 7) If any voltage is not as specified, check appropriate circuit test.

TILT & TELESCOPIC ECU PIN VOLTAGE