Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT FUSE (MPX-IG)
1. Remove the MPX-IG fuse from the passenger side junction block.
2. Measure the resistance of the fuse.
  Standard resistance:
  
  Below 1 Ω
NG: REPLACE FUSE

OK: Go to next step

CHECK WIRE HARNESS (SLIDING ROOF CONTROL ECU - BATTERY)

Disconnect the S18 ECU connector.

Fig 1: Identifying S18 ECU Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance and voltage of the wire harness side connector.

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
S18-18 (SIG) - Body ground	Ignition switch OFF	Below 1 V
S18-18 (SIG) - Body ground	Ignition switch ON	10 to 14 V

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: REPLACE SLIDING ROOF CONTROL ECU