System Operation Check

Trouble shooting of a power seat system complaint begins with verification of the customer problem. If problem occurs, go to step 3. 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.
Inspect the multiplex communication system and confirm that there is no trouble by the basic inspection and DTC check. See PRE-CHECK under SELF-DIAGNOSTIC under MULTIPLEX COMMUNICATION SYSTEM article in COMMUNICATION DEVICES.

Determine problem symptom. See PROBLEM SYMPTOM INDEX table.

PROBLEM SYMPTOM INDEX

Symptom

Suspected Area ⁽¹⁾

Both Driver & Passenger Power Seats Do Not Operate (Door Lock Does Not Operate)

⁽²⁾⁽³⁾

Driver's Seat Does Not Operate

⁽⁴⁾⁽⁵⁾⁽³⁾

Passenger's Seat Does Not Operate

⁽⁴⁾⁽⁶⁾⁽³⁾

Slide Operation Does Not Operate

⁽⁵⁾⁽⁶⁾⁽³⁾⁽⁷⁾

Front Vertical Operation Does Not Operate

⁽⁵⁾⁽⁶⁾⁽³⁾⁽⁸⁾

Lifter Operation Does Not Operate

⁽⁵⁾⁽⁶⁾⁽³⁾⁽⁹⁾

Reclining Operation Does Not Operate

⁽⁵⁾⁽⁶⁾⁽³⁾⁽¹⁰⁾

Lumbar Support Operation Does Not Operate

⁽⁵⁾⁽³⁾⁽¹¹⁾

Both Manual & Return Functions Do Not Operation (All Functions)

⁽¹²⁾⁽¹³⁾⁽¹⁴⁾⁽¹⁵⁾

Both Manual & Return Functions Do Not Operate (One Function Only)

⁽¹⁴⁾⁽¹⁵⁾

One Or All Functions Do Not Operate For Manual Operation Only

⁽¹³⁾⁽¹⁵⁾

Memory Function Does Not Operate

⁽¹⁶⁾⁽¹⁷⁾⁽¹⁵⁾⁽¹⁸⁾

Return Operation Does Not Stop When Brake Pedal Is Depressed

⁽¹⁵⁾⁽¹⁸⁾

Only Return Function Does Not Operate Or Operates A Little, Then Stops (All Return Functions)

⁽¹⁹⁾⁽²⁰⁾⁽¹⁵⁾⁽¹⁸⁾

Only Return Function Does Not Operate Or Operates A Little, Then Stops (Only One Return Function)

⁽²¹⁾⁽¹⁵⁾

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

⁽²⁾	Check the ALT M-fuse.

⁽³⁾	Check the wire harness.

⁽⁴⁾	Check the POWER fuse located in the left hand cowl side junction block behind the left kick panel.

⁽⁵⁾	Check the driver power seat switch. See POWER SEAT SWITCH under COMPONENT TESTS.

⁽⁶⁾	Check the passenger power seat switch. See POWER SEAT SWITCH under COMPONENT TESTS.

⁽⁷⁾	Check the driver and passenger slide motor. See POWER SEAT MOTOR under COMPONENT TESTS.

⁽⁸⁾	Check the driver and passenger front vertical motor. See POWER SEAT MOTOR under COMPONENT TESTS.

⁽⁹⁾	Check the driver and passenger lifter motor. See POWER SEAT MOTOR under COMPONENT TESTS.

⁽¹⁰⁾	Check the driver and passenger reclining motor. See POWER SEAT MOTOR under COMPONENT TESTS.

⁽¹¹⁾	Check the driver lumbar support motor. LUMBAR SUPPORT MOTOR under COMPONENT TESTS.

⁽¹²⁾	Check the +B power source circuit. See +B POWER SOURCE CIRCUIT under CIRCUIT TESTS.

⁽¹³⁾	Check the power seat switch circuit. See POWER SEAT SWITCH CIRCUIT under CIRCUIT TESTS.

⁽¹⁴⁾	Check the motor circuit. See MOTOR CIRCUIT under CIRCUIT TESTS.

⁽¹⁵⁾	Check the power seat control ECU.

⁽¹⁶⁾	Check the power seat memory switch circuit. See MEMORY SWITCH CIRCUIT under CIRCUIT TESTS in BODY CONTROL SYSTEM article in COMMUNICATION DEVICES.

⁽¹⁷⁾	Check the ignition switch circuit. See IGNITION SWITCH CIRCUIT under CIRCUIT TESTS.

⁽¹⁸⁾	Check the instrument panel ECU (body ECU).

⁽¹⁹⁾	Check the ECU power source circuit. See ECU POWER SOURCE CIRCUIT under CIRCUIT TESTS.

⁽²⁰⁾	Check the position sensor power source circuit. See POSITION SENSOR POWER SOURCE CIRCUIT under CIRCUIT TESTS.

⁽²¹⁾	Check the position sensor circuit. See POSITION SENSOR CIRCUIT under CIRCUIT TESTS.

Inspect the circuits of the power and memory seat system. See CIRCUIT TESTS . If the trouble still reappears in the power seat system, even though there are no abnormalities in any of the other circuits, check and replace the power seat position ECU as the last step.
After repairs have been completed, confirm that problem has been eliminated. Operate the 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.