Circuit Description
The potentiometer type position sensor that sets this DTC is an internal part of the seat directional motor. It receives a 5-volt reference and low reference from the memory seat module (MSM). The sensor sends a voltage signal that is pulled up to voltage by the MSM. This voltage signal varies with the movement of the seat. Then based on this voltage signal, the MSM determines the position of the seat.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC B1825 Seat Recline Position Sensor Circuit |
| • | DTC B1850 Seat Lumbar Horizontal Position Sensor Circuit |
| • | DTC B1860 Seat Lumbar Vertical Position Sensor Circuit |
| • | DTC B2355 Seat Front Vertical Position Sensor Circuit |
| • | DTC B2365 Seat Rear Vertical Position Sensor Circuit |
| • | DTC B2375 Seat Assembly Horizontal Position Sensor Circuit |
DTC Symptom | DTC Symptom Descriptor |
|---|---|
08 | Out of Range -- Exceeds Lower or Upper Limits |
Conditions for Running the DTC
The MSM must be powered and cannot have B1325 Battery Voltage Low as an active DTC for this DTC to set.
Conditions for Setting the DTC
If the MSM sees the voltage signal from this sensor as either lower than 0.25 volts or higher than 4.75 volts, the sensor will be considered out of range and the MSM will set this DTC.
Action Taken When the DTC Sets
The MSM disables all memory recall commands of the motor monitored by the sensor. The motor will respond to manual positioning commands.
Conditions for Clearing the DTC
The MSM will clear the DTC when it detects that the voltage from the sensor signal circuit is between 0.25 volts and 4.75 volts.
Diagnostic Aids
| • | The MSM is referenced in the Tech 2 as the driver position module (DPM) for this vehicle. |
| • | All position sensors use common low reference and 5-volt reference circuits. |
| • | If the 5-volt reference circuit is shorted to voltage multiple codes will set. |
| • | If the 5-volt reference circuit is shorted to ground multiple codes will set. |
| • | If the sensor low reference circuit is open multiple codes will set. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests for the proper operation of the circuit in the high voltage range.
-
This step tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Driver Seat Schematics Connector End View Reference: Power Seat Connector End Views | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||
2 |
Does the scan tool indicate that the Sensor parameter is within the specified range? | 0.25-4.75 V | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 | ||||||
Does the scan tool indicate that the Sensor parameter is greater than the specified value? | 4.75 V | Go to Step 4 | Go to Step 5 | |||||||
Does the scan tool indicate that the Sensor parameter is less than the specified value? | 0.25 V | Go to Step 6 | Go to Step 8 | |||||||
5 | Test the 5-volt reference circuit of the sensor for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 7 | ||||||
6 | Test the 5-volt reference circuit of the sensor for the following conditions:
Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 11 | ||||||
7 | Test the signal circuit of the sensor for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 12 | ||||||
8 | Test the signal circuit of the sensor for the following conditions:
Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 9 | ||||||
9 | Test the low reference circuit of the sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 10 | ||||||
10 | Test the 5-volt reference circuit of the sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 12 | ||||||
11 | Inspect for poor connections at the harness connector of the sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 13 | ||||||
12 | Inspect for poor connections at the harness connector of the memory seat module (MSM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 14 | ||||||
13 | Replace the appropriate lumbar. Refer to Front Seat Lumbar Support Replacement . Did you complete the replacement? | -- | Go to Step 15 | -- | ||||||
14 | Replace the MSM. Refer to Control Module References . Did you complete the replacement? | -- | Go to Step 15 | -- | ||||||
15 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||
