Circuit/System Testing
B1825
- Ignition OFF, disconnect the X2 harness connector at the seat recline motor.
- Ignition OFF, test for less than 2 ohms of resistance between the low reference circuit terminal 1 and ground.
- If greater than 2 ohms, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 3 and ground.
- If less than 4.8 volts, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If greater than 5.2 volts, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Verify the scan tool Driver Seat Recline Sensor parameter is less than 2.0 volts.
- If greater than 2.0 volts, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the MSM.
- Install a 3A fused jumper wire between the signal circuit terminal 2 and the 5-volt reference circuit terminal 3. Verify the scan tool Driver Seat Recline Sensor parameter is greater than 4.65 volts.
- If less than 4.65 volts, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If all circuits test normal, test or replace the seat recline position sensor.
B2355, B2365, B2375
- Ignition OFF, disconnect the X2 harness connector at the seat adjuster motor assembly.
- Ignition OFF, test for less than 2 ohms of resistance between the low reference circuit terminal 2 and ground.
- If greater than 2 ohms, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 6 and ground.
- If less than 4.8 volts, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If greater than 5.2 volts, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Verify the appropriate scan tool Driver Seat Sensor parameter is less than 2.0 volts.
- If greater than 2.0 volts, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Seat front vertical position sensor terminal 1
- Seat rear vertical position sensor terminal 5
- Seat horizontal position sensor terminal 3
- If greater than 2.0 volts, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Install a 3A fused jumper wire between the signal circuit and the 5-volt reference circuit terminal 6. Verify the appropriate scan tool Driver Seat position sensor parameter is greater than 4.65 volts.
- Seat front vertical position sensor terminal 1
- Seat rear vertical position sensor terminal 5
- Seat horizontal position sensor terminal 3
- If less than 4.65 volts, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If all circuits test normal, test or replace the seat adjuster motor assembly.
B1850, B1860
- Ignition OFF, disconnect the X2 harness connector at the seat lumbar motor assembly.
- Ignition OFF, test for less than 2 ohms of resistance between the low reference circuit terminal C and ground.
- If greater than 2 ohms, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.
- If less than 4.8 volts, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If greater than 5.2 volts, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Verify the appropriate scan tool Lumbar Sensor parameter is less than 2.0 volts.
- If greater than 2.0 volts, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Lumbar vertical position sensor terminal B
- Lumbar horizontal position sensor terminal D
- If greater than 2.0 volts, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
- Install a 3A fused jumper wire between the signal circuit and the 5-volt reference circuit terminal C. Verify the appropriate scan tool Lumbar Sensor parameter is greater than 4.65 volts.
- Lumbar vertical position sensor terminal B
- Lumbar horizontal position sensor terminal D
- If less than 4.65 volts, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
- If all circuits test normal, test or replace the lumbar motor assembly.