Power Seat Inoperative (Without Memory - A45)
Power Seat Inoperative (Without Memory - A45)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
Circuit/System Description
Power seat without memory is completely controlled through the seat adjuster switch. Battery voltage is supplied at all times to the seat adjuster switch from the 30 amp PWR SEATS circuit breaker that is located in the right rear fuse block. When the seat adjuster switches are in an inactive state, the switch contacts are closed to the switch ground circuit.
All seat motors are reversible. For example, when the seat horizontal forward switch is pressed to move the entire seat forward, battery voltage is applied through the switch contacts and the seat horizontal motor forward control circuit to the motor. The motor is grounded through the horizontal motor rearward switch contacts and the horizontal motor rearward control circuit to the motor. The motor runs in order to drive the entire seat forward until the switch is released. Moving the entire seat rearward works similarly to moving the entire seat forward, except that battery positive voltage and ground are applied on opposite circuits causing the motor to run in the opposite direction. All seat motors are powered this way.
Reference Information
Schematic Reference
* Driver Seat Schematics (Driver Seat Schematics)
* Passenger Seat Schematics (Passenger Seat Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Power Seats System Description and Operation (Folding Seat) (Power Seats System Description and Operation (Folding Seat))Power Seats System Description and Operation (Front Seat) (Power Seats System Description and Operation (Front Seat))
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning)
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.
2. Ignition OFF, test for less than 1 ohm between the ground circuit terminal D and ground.
• If not the specified value, test the ground circuit for an open/high resistance.
3. Verify that a test lamp illuminates between the B+ circuit terminal A and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
4. Connect the harness connector at the seat adjuster switch.
5. Disconnect the harness connector at the inoperative seat motor.
6. Connect a test lamp between the motor control circuits terminal A and terminal B.
7. Activate the appropriate seat switch to the FORWARD/UP and REARWARD/DOWN directions. The test lamp should turn ON while activating the switch in the both directions.
• If the test lamp remains OFF for either direction, test the motor control circuits for a short to ground or an open/high resistance. If the circuits test normal, test or replace the seat adjuster switch.
8. If all circuits test normal, replace the inoperative seat motor.
Component Testing
Driver Seat Adjuster Switch Test
1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.
2. Test for infinite resistance between each control terminal (A, B, D, E and J-M) and the B+ terminal F with the switch in the open position.
• If less than the specified value, replace the seat adjuster switch.
3. Test for less than 1 ohm between each control terminal (A, B, D, E and J-M) and the B+ terminal F with the switch in the closed position.
• If greater than the specified range, replace the seat adjuster switch.
4. Test for less than 1 ohm between each control terminal (A, B, D, E and J-M) and the ground terminal C with the switch in the open position.
• If greater than the specified range, replace the seat adjuster switch.
Passenger Seat Adjuster Switch Test
1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.
2. Test for infinite resistance between each control terminal (B, C, and E-K) and the B+ terminal A with the switch in the open position.
• If less than the specified value, replace the seat adjuster switch.
3. Test for less than 1 ohm between each control terminal (B, C, and E-K) and the B+ terminal A with the switch in the closed position.
• If greater than the specified range, replace the seat adjuster switch.
4. Test for less than 1 ohm between each control terminal (B, C, and E-K) and the ground terminal D with the switch in the open position.
• If greater than the specified range, replace the seat adjuster switch.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Power Seat Switch Replacement (Power Seat Switch Replacement)
* Seat Adjuster Motor Replacement - Horizontal (Seat Adjuster Motor Replacement - Horizontal)
* Seat Adjuster Motor Replacement - Vertical (Seat Adjuster Motor Replacement - Vertical)
* Front Seat Recliner Actuator Motor Replacement (Front Seat Recliner Actuator Motor Replacement)