Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit Description
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.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.