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B2105



DTC B1825, B1850, B1860, B2105, B2355, B2365, or B2375

DTC DESCRIPTORs

DTC B1825 01
Seat Recline Position Sensor Circuit Short to Battery

DTC B1825 06
Seat Recline Position Sensor Circuit Short to Ground or Open

DTC B1825 5A
Seat Recline Position Sensor Direction of Motion Reversed

DTC B1850 01
Seat Lumbar Horizontal Position Sensor Circuit Short to Battery

DTC B1850 06
Seat Lumbar Horizontal Position Sensor Circuit Short to Ground or Open

DTC B1850 5A
Seat Lumbar Horizontal Position Sensor Direction of Motion Reversed

DTC B1860 01
Seat Lumbar Vertical Position Sensor Circuit Short to Battery

DTC B1860 06
Seat Lumbar Vertical Position Sensor Circuit Short to Ground or Open

DTC B1860 5A
Seat Lumbar Vertical Position Sensor Direction of Motion Reversed

DTC B2355 01
Left Front Seat Front Vertical Position Sensor Circuit Short to Battery

DTC B2355 06
Left Front Seat Front Vertical Position Sensor Circuit Short to Ground or Open

DTC B2355 5A
Left Front Seat Front Vertical Position Sensor Direction of Motion Reversed

DTC B2365 01
Left Front Seat Rear Vertical Position Sensor Circuit Short to Battery

DTC B2365 06
Left Front Seat Rear Vertical Position Sensor Circuit Short to Ground or Open

DTC B2365 5A
Left Front Seat Rear Vertical Position Sensor Direction of Motion Reversed

DTC B2375 01
Left Front Seat Assembly Horizontal Position Sensor Circuit Short to Battery

DTC B2375 06
Left Front Seat Assembly Horizontal Position Sensor Circuit Short to Ground or Open

DTC B2375 5A
Left Front Seat Assembly Horizontal Position Sensor Direction of Motion Reversed

DIAGNOSTIC FAULT INFORMATION







Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview

CIRCUIT/SYSTEM DESCRIPTION
The position sensor that set this diagnostic trouble code (DTC) is either attached to the seat directional motor drive cable or directly to the motor it monitors. It receives a 5-volt reference and ground from the memory seat module (MSM). The sensor sends a voltage signal that varies with the movement of the seat through the signal circuit to the MSM. Then based on this voltage signal, the MSM determines the position of the seat.

CONDITIONS FOR RUNNING THE DTC
The MSM must be powered.

CONDITIONS FOR SETTING THE DTC

B1825/B1850/B1860/B2355/B2365/B2375 01
If the MSM sees the analog input from this sensor is greater than 4.65 volts, the sensor will be considered out of range and the MSM will set this DTC.

B1825/B1850/B1860/B2355/B2365/B2375 06
If the MSM sees the analog input from this sensor is less than 0.27 volt , the sensor will be considered out of range and the MSM will set this DTC.

B1825/B1850/B1860/B2355/B2365/B2375 5A
This DTC will set, if the MSM is controlling a motor in one direction and it's position sensor is tracking the motor in the opposite direction. The sensor is either mounted or wired incorrectly, or the polarity of the motor control circuits are reversed.

ACTION TAKEN WHEN THE DTC SETS
All memory recall and seat massage functions will be disabled.

CONDITIONS FOR CLEARING THE DTC
- The current DTC will clear and set to history, when the MSM sees the analog input from the sensor as between 0.27 volt and 4.65 volts and the ignition is cycled OFF then back to ACC or RUN.
- The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

DIAGNOSTIC AIDS
- All position sensors use common ground and 5-volt reference circuits.
- If the 5-volt reference circuit is shorted to voltage multiple position sensor codes will set.
- If the 5-volt reference circuit is shorted to ground multiple position sensor codes will set.
- If the sensor ground circuit is open multiple codes will set.
- DTC failure type 5A will set if the sensor setting this DTC is either mounted or wired incorrectly, or the polarity of the motor control circuits are reversed.

CIRCUIT/SYSTEM VERIFICATION
Ignition ON, observe the scan tool Driver Seat and Lumbar Position Sensor parameters. The readings should be between 0.27 volt and 4.65 volts and change while adjusting seat and lumbar positions.

CIRCUIT/SYSTEM TESTING

B1825
1. Ignition OFF, disconnect the (C2) harness connector at the seat recline motor.
2. Ignition OFF, test for less than 2 ohms of resistance between the low reference circuit terminal 3 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.
3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 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.
4. Verify the scan tool Driver Seat Recline Sensor parameter is less than 2 volts.
- If greater than 2 volts, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the MSM.
5. Install a 3A fused jumper wire between the signal circuit terminal 2 and the 5-volt reference circuit terminal 1. 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.
6. If all circuits test normal, test or replace the seat recline position sensor.

B2355/B2365/B2375
1. Ignition OFF, disconnect the (C2) harness connector at the seat adjuster motor assembly.
2. 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.
3. 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.
4. Verify the appropriate scan tool Driver Seat Sensor parameter is less than 2 volts.
- If greater than 2 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
5. 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.
6. If all circuits test normal, test or replace the seat adjuster motor assembly.

B1850/B1860
1. Ignition OFF, disconnect the (C2) harness connector at the seat lumbar motor assembly.
2. Ignition OFF, test for less than 2 ohms of resistance between the low reference circuit terminal A 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.
3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C 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.
4. Verify the appropriate scan tool Lumbar Sensor parameter is less than 2 volts.
- If greater than 2 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
5. 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.
6. If all circuits test normal, test or replace the lumbar motor assembly.

REPAIR INSTRUCTIONS
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
- Front Seat Adjuster Replacement
- Power Recliner Sensor Replacement - Front
- Lumbar Replacement - Front Seat (w/AL2) Lumbar Replacement - Front Seat (w/AM3)
- Control Module References for memory seat module replacement, setup, and programming Programming and Relearning
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