Circuit Description
The seat adjuster motors are controlled by the memory seat module through the adjuster motor supply circuits. Adjuster motor operation occurs when the memory seat module switches one of the adjuster motor supply circuits to battery positive voltage and the other to ground. The adjuster motors are reversible and the direction of the adjuster motor rotation is determined by which of the adjuster motor supply circuits is switched to battery positive voltage and which is grounded.
The seat adjuster motors are equipped with position sensors. The position sensors are supplied with a 5 volt reference circuit and low reference circuit from the memory seat module. The position sensor signal circuits are supplied 5 volts through a resistor and monitored within the memory seat module. The position sensor signal circuit voltage is pulled low by the position sensor and varies from 0 to 5 volts depending on the seat position. The memory seat module uses the position sensor signal voltages to determine the seat position when storing or recalling seat position settings.
Conditions for Setting the DTC
The following conditions will cause a seat adjuster motor DTC to set.
| • | The position sensor signal voltage to the memory seat module is not within 0.1 to 4.7 volts. |
| • | The memory seat module attempts to operate a seat adjuster motor and no change is observed through the position sensor. |
| • | A seat adjuster switch input to the memory seat module is always active. |
Action Taken When the DTC Sets
| • | Memory seat recall functions will be disabled. |
| • | The seat adjuster motor may be disabled. |
Conditions for Clearing the DTC
| • | A current DTC will be stored as a history code when the conditions for setting the DTC are no longer present. |
| • | A history DTC will be cleared after 20 error free ignition cycles or by using the scan tool clear DTCs feature. |
| • | Some intermittent DTCs will be cleared when the conditions for setting the DTC are no longer present, others will be cleared after 20 error free ignition cycles or by using the scan tool clear DTCs feature. |
Diagnostic Aids
| • | Inspect for mechanical conditions which may prevent the seat adjuster motor from operating properly. |
| • | Inspect the connectors at the memory seat module for damage or poor terminal connections. |
| • | If the fault is not current the problem may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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This step is testing the ability of the memory seat module to interpret the signal circuit in the high voltage range.
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This step is testing the ability of the memory seat module to interpret the signal circuit in the low voltage range.
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This step determines if the DTC is set due to an always active adjuster switch input.
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This step is testing the ability of the memory seat module to operate the seat adjuster motor.
Step
| Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Memory Seats Schematics | ||||
1 | Did you perform the Power Seat System Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Is the DTC status displayed as current? | -- | Go to Step 3 | Go to Step 7 |
3 |
Is the voltage within the specified values? | 0.1-4.7 V | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 4 |
Is the voltage within the specified values? | 4.7-5.0 V | Go to Step 5 | Go to Step 13 | |
Is the voltage at or near the specified value? | 0.0 V | Go to Step 6 | Go to Step 12 | |
6 | Inspect and repair any damage to the position sensor harness and connector. Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 11 |
Are either of the adjuster switches displayed as active? | -- | Go to Step 8 | Go to Step 9 | |
8 | Disconnect the seat adjuster switch connector to the memory seat module. Are either of the adjuster switches displayed as active? | -- | Go to Step 13 | Go to Step 14 |
Does the test lamp illuminate while the switch is pressed in both directions? | -- | Go to Step 11 | Go to Step 10 | |
10 | Test the memory seat module high current ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 13 |
11 | Inspect and repair any damage to the adjuster motor harness and connector. Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 12 |
12 | Replace the inoperative adjuster motor. Refer to Power Seat Adjuster Mechanism Replacement or Recliner Motor Replacement - Front Power . Is the repair complete? | -- | Go to Step 16 | -- |
13 | Replace the memory seat module. Refer to Memory Seat Control Module Replacement and Memory Seat Control Module Programming . Is the repair complete? | -- | Go to Step 16 | -- |
14 | Inspect and repair any damage to the seat adjuster switch harness and connector. Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 15 |
15 | Replace the seat adjuster switch assembly. Refer to Power Seat Switch Replacement . Is the repair complete? | -- | Go to Step 16 | -- |
16 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
