Circuit/System Testing

Seat Adjuster Switch Circuit Test

1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal E and ground.
   • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
3. Install a 3A fused jumper wire between the appropriate signal circuit listed below and the B+ circuit terminal E. Verify the scan tool seat switch parameter is Active.
   • Front vertical upward switch terminal K
   • Front vertical downward switch terminal J
   • Rear vertical upward switch terminal H
   • Rear vertical downward switch terminal G
   • Horizontal forward switch terminal D
   • Horizontal rearward switch terminal C
   • Recline forward switch terminal F
   • Recline rearward switch terminal A
   • If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
4. If all circuits test normal, test or replace the seat adjuster switch.

Seat Motor Control Circuit Test

1. Ignition OFF, disconnect the X1 harness connector at the MSM.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal B and ground.
   • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
3. Ignition OFF, connect the X1 harness connector at the MSM and disconnect the X1 harness connector at the seat adjuster motor assembly.
4. Connect a test lamp between the appropriate control circuits listed below:
   • Seat horizontal motor terminal 3 and terminal 6
   • Seat front vertical motor terminal 2 and terminal 5
   • Seat rear vertical motor terminal 1 and terminal 4
5. Ignition ON, command the appropriate seat motor in the Up/Down or Forward/Rearward directions with a scan tool. The test lamp should turn ON when commanding the up and down or forward and rearward states.
   • If the test lamp remains OFF during either of the commands, test the control circuits for a short to ground or an open/high resistance. If the circuits test normal replace the MSM.
6. If all circuits test normal, test or replace the seat motor.

Recline Motor Control Circuit Test

1. Ignition OFF, disconnect the X1 harness connector at the recline motor.
2. Connect a test lamp between control circuit terminal A and control circuit terminal B.
3. Ignition ON, command the Recline Forward/Rearward with a scan tool. The test lamp should turn ON when commanding the forward and rearward states.
   • If the test lamp remains OFF during either of the commands, test the control circuits for a short to ground or an open/high resistance. If the circuits test normal, replace the MSM.
4. If all circuits test normal, test or replace the recline motor.