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Home >> Toyota >> 2003 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 455 (Front Power Seat Control System (With Memory) - Diagnosis) >> Ecu Power Source Circuit >> Circuit Description
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Circuit Description

WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.

The position control ECU is contained in the switch assy.

When a switch is activated during manual operation, all other signals are ignored, i.e. if more than one ON signal from the switches are input at the same time, all of them are ignored. However, if the front vertical switch signal and the lifter switch are activated simultaneously, only the lifter switch can be activated. During automatic operation, a manual switch input overrides any other operations, i.e. automatic operations stop and the manual input operation are accepted. For example, if during a seat store/restore operation, a manual switch input is activated, the previous operation will cease and manual operation will be performed. After the manual operation is performed, the previous automatic operation will not resume. Adjustable pedal and power mirror store/restore operation is unaffected by manual switch inputs.

The position control ECU & switch assy disallows the restore operation of the power seat when the system detects that the voltage of terminal SYSB is less than 8 V for 0.3 seconds or is more than 10 V for 30 seconds.

The following circuit is a power source circuit of the position control ECU & switch assy.

HINT: Manual adjustment of the slide reclining lumbar can be performed even when the ECU is not functional if current is allowed to flow into terminals +B and SYSB.

Lumbar operation can always be performed.