Circuit Description
The seat adjuster motors are equipped with potentiometer type position sensors used by the memory seat module (MSM) to determine the seat position. The motor position sensors are supplied with 5-volt reference and ground circuits from the MSM. The position sensor signal circuits are referenced from ground within the MSM. The signal voltages monitored by the MSM range from 0.24-4.75 volts and are determined by the wiper locations on the resistors within the position sensors. The position sensor circuit voltage levels are used by the MSM to determine the position of the seat when storing or recalling memory position settings.
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 B2355 Seat Front Vertical Position Sensor Circuit |
| • | DTC B2365 Seat Rear Vertical Position Sensor Circuit |
| • | DTC B2375 Seat Assembly Horizontal Position Sensor Circuit |
Conditions for Running the DTC
The system voltage must be between 9-16 volts.
Conditions for Setting the DTC
The MSM detects the position sensor signal circuit under 0.24 volts or over 4.75 volts.
Action Taken When the DTC Sets
Memory functions will be disabled as long as the fault is current.
Conditions for Clearing the DTC
| • | The DTC will be current for as long as the fault is present. |
| • | When the fault is no longer present the DTC will be a history status code. |
| • | The history DTC will be cleared after 100 error free ignition cycles, or by using the scan tool clearing DTCs feature. |
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Memory Seats Schematics Connector End View Reference: Power Seat Connector End Views | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||
2 |
Does the scan tool indicate that the position sensor parameter is within the specified range? | 0.2-4.7 V | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 | ||||||
3 |
Does the voltage measure within the specified range? | 4.7-5 V | Go to Step 5 | Go to Step 4 | ||||||
4 | Test the 5-volt reference circuit of the position sensor for the following conditions:
Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 | ||||||
5 |
Does the scan tool indicate that the position parameter is within the specified range? | 4.7-5 V | Go to Step 7 | Go to Step 6 | ||||||
6 | Test the signal circuit of the position sensor for the following conditions:
Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 | ||||||
7 | Test the low reference circuit of the position sensor for an open or high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 8 | ||||||
8 | Inspect for poor connections at the harness connector of the position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 | ||||||
9 | Inspect for poor connections at the harness connector of the MSM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 | ||||||
10 | Replace the seat position sensor. Refer to Power Seat Adjuster Mechanism Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- | ||||||
11 | Replace the MSM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||||
12 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||
