SELF-DIAGNOSTICS
| WARNING | Deactivate air bag system before performing any service operation. See AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy. |
When diagnosing multiplex control system, perform INSTRUMENT ECU and OPEN DOOR INDICATOR LIGHT inspection procedures first to ensure DTCs can be retrieved. See PRELIMINARY INSPECTION .
Scan Tool Method
OBD-II DTCs from multiplex self-diagnostic system are retrieved through Data Link Connector (DLC) No. 3. DLC No. 3 is located under left side of instrument panel. Connect scan tool to DLC No. 3. Turn ignition on. See scan tool manufacturer's instructions. Retrieve DTCs. See MULTIPLEX DTC DEFINITIONS . If any DTCs are present, perform appropriate test. See DIAGNOSTIC TESTS .
| OBD-II DTC/2-Digit DTC (1) | Definition |
|---|---|
| B1213/13 | Tilt/Telescopic ECU Communication |
| B1215/15 | Door System Communication Bus Malfunction (Short Circuit) |
| B1272/72 | Power Seat ECU Communication |
| B1276/76 | Remote Control Mirror ECU Communication |
| (1) For diagnosis, see appropriate diagnostic procedure under DIAGNOSTIC TESTS . | |
| (1) | For diagnosis, see appropriate diagnostic procedure under DIAGNOSTIC TESTS . |
MULTIPLEX DTC DEFINITIONS
CLEARING DIAGNOSTIC TROUBLE CODES
Note. After repairs, DTCs are cleared from memory automatically during next code retrieval if multiplex system operation is normal.
DIAGNOSTIC TESTS
| WARNING | Deactivate air bag system before performing any service operation. See AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy. |
Diagnostic Procedure
- Check operation of power tilt/telescopic steering column. See POWER TILT STEERING COLUMN SYSTEMS - LX470 article. If operation is okay, go to next step. If operation is not okay, replace power tilt/telescopic ECU.
- Disconnect instrument ECU 18-pin connector "B", tilt/telescopic ECU 8-pin connector T9, and remote control mirror ECU connector. (Scheme 2)- (Scheme 4).
- Check continuity of Sky Blue wire and Red wire between instrument ECU connector "B" terminal No. 9 and tilt/telescopic ECU 8-pin connector terminal No. 8. Check continuity of Blue wire between tilt/telescopic ECU 8-pin connector terminal No. 3 and remote control mirror ECU connector terminal No. 13. If continuity exists, replace tilt/telescopic ECU. If continuity does not exist, repair wiring harness as necessary. See «WIRING DIAGRAMS»(ref-8893-S14963227612000092800000).
Scheme 2
Scheme 3
Scheme 4
- Disconnect remote control mirror ECU connector. (Scheme 4) Check for DTCs. If DTC B1215/15 is not displayed, replace remote control mirror ECU. If DTC B1215/15 is displayed, go to next step.
- Connect remote control mirror ECU. Disconnect tilt/telescopic ECU 8-pin connector T9. (Scheme 3) Check for DTCs. If DTC B1215/15 is not displayed, replace tilt/telescopic ECU. If DTC B1215/15 is displayed, go to next step.
- Connect tilt/telescopic ECU 8-pin connector. Disconnect power seat ECU 22-pin connector "A". (Scheme 5) Check for DTCs. If DTC B1215/15 is not displayed, replace power seat ECU. If DTC B1215/15 is displayed, go to next step.
- Disconnect remote control mirror ECU connector. Check for DTCs. If DTC B1215/15 is not displayed, repair wiring harness between remote control mirror ECU and instrument ECU. See «WIRING DIAGRAMS»(ref-8893-S14963227612000092800000). If DTC B1215/15 is displayed, go to next step.
- Disconnect tilt/telescopic ECU 8-pin connector T9. Check for DTCs. If DTC B1215/15 is not displayed, repair wiring harness between remote control mirror ECU and tilt/telescopic ECU. See «WIRING DIAGRAMS»(ref-8893-S14963227612000092800000). If DTC B1215/15 is displayed, go to next step.
- Disconnect power seat ECU 22-pin connector. Check for DTCs. If DTC B1215/15 is not displayed, repair wiring harness between power seat ECU and tilt/telescopic ECU. See «WIRING DIAGRAMS»(ref-8893-S14963227612000092800000). If DTC B1215/15 is displayed, replace instrument ECU and retest.
Scheme 5
- Check operation of power seat. If power seat functions properly, go to next step. If power seat does not function properly, replace power seat ECU and retest.
- Disconnect instrument ECU 22-pin connector "A", power seat ECU 22-pin connector "A", and tilt/telescopic ECU connector T9. (Scheme 2), (Scheme 3) and (Scheme 5).
- Check continuity of Sky Blue wire and Black wire between instrument ECU connector terminal No. 12 and power seat connector terminal No. 10. Check continuity of Black/White wire and Blue wire between power seat ECU terminal No. 11 and tilt/telescopic ECU terminal No. 3. If continuity exists, replace power seat ECU. If continuity does not exist, repair wiring harness as necessary. See «WIRING DIAGRAMS»(ref-8893-S14963227612000092800000).
- Check operation of power mirrors. If power mirrors function properly, go to next step. If power mirrors do not function properly, replace remote control mirror ECU and retest.
- Disconnect remote control mirror ECU connector, and tilt/telescopic ECU 8-pin connector T9. (Scheme 3)and (Scheme 4).
- Check continuity of Sky Blue wire and Red wire between instrument ECU 18-pin connector "B" terminal No. 9 and tilt/telescopic ECU 8-pin ECU connector T9 terminal No. 8. Check continuity of Blue wire between remote control mirror ECU connector terminal No. 13 and tilt/telescopic ECU 8-pin connector T9 terminal No. 3. If continuity exists, replace remote control mirror ECU. If continuity does not exist, repair wiring harness as necessary. See «WIRING DIAGRAMS»(ref-8893-S14963227612000092800000).
