System Operation Check

WARNING: This page is about a different car, the 2003 Lexus ES 300 and 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.

Trouble shooting of a moon roof system complaint begins with verification of the customer problem. If problem occurs, diagnose by symptom. See PROBLEM SYMPTOMS table. If problem does not occur, go to next step.
If problem does not occur, review conditions under which problem occurred for customer and try to duplicate those conditions. For example, if the problem occurs on rainy days or during high humidity conditions, sprinkle water onto vehicle and see if malfunction occurs. DO NOT sprinkle water directly into engine compartment or onto electronic components. Visually inspect for signs of mechanical and electrical damage. Inspect for blown fuses and damaged relays. Inspect for loose or corroded connections, damaged wiring harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any aftermarket electronic equipment is properly installed. If fault is found, repair as necessary. If problem still cannot be created, diagnose by symptom. See PROBLEM SYMPTOMS table.
After repairs have been completed, confirm that problem has been eliminated. Operate system under same conditions recorded for original complaint. If problem is no longer present, repair has corrected problem. If problem is still present, further diagnosis and repair is required.

PROBLEM SYMPTOMS

Symptom

Suspected Area ⁽¹⁾

Moon Roof System Does Not Operate

⁽²⁾⁽³⁾⁽⁴⁾⁽⁵⁾⁽⁶⁾

Moon Roof System Stops Operation Half Way (No Foreign Object Is In The Motor)

⁽³⁾⁽⁴⁾⁽⁵⁾

Rear Sun Shade Does Not Operate By Manual Operation

⁽⁷⁾⁽⁸⁾

Rear Sun Shade Does Not Operate Automatically When The Shift Lever Is Moved Into The R Range (Reverse)

⁽⁷⁾⁽⁸⁾

⁽¹⁾	Perform test procedures in order listed under suspected area.

⁽²⁾	Check PWR NO. 1 fuse.

⁽³⁾	Check the moon roof motor switch. See ROOF CONSOLE BOX ASSEMBLY under COMPONENT TESTS.

⁽⁴⁾	Check the moon roof drive gear. See ON-VEHICLE INSPECTION under COMPONENT TESTS.

⁽⁵⁾	Check the wire harness. See ON-VEHICLE INSPECTION under COMPONENT TESTS.

⁽⁶⁾	Check the faulty sliding of the moon roof.

⁽⁷⁾	Check the rear sun shade switch. See REAR SUN SHADE SWITCH under COMPONENT TESTS.

⁽⁸⁾	Check the rear sun shade relay. See REAR SUN SHADE RELAY under COMPONENT TESTS.