Circuit Description
The seat adjuster motors are controlled by the memory seat module through the adjuster motor control circuits. In an inactive state both of the motor control circuits are grounded within the memory seat module. In an active state the memory seat module switches the appropriate motor control circuit to battery positive voltage. The direction of the adjuster motor rotation is determined by which of the motor control circuits is switched to battery positive voltage while the other remains grounded. During adjuster motor operation the memory seat module also monitors the current flow through the motor control circuits.
The memory seat module monitors the positions of the horizontal, front vertical, and rear vertical adjuster motors using hall effect type position sensors. The hall effect position sensors are supplied with 5-volt reference and ground circuits from the memory seat module. The position sensor signal circuits are supplied 5-volts through a resistor then monitored within the memory seat module. During adjuster motor operation the hall effect position sensor provides a single pulse for every adjuster motor shaft rotation. The memory seat module counts the pulses from the position sensor signal circuits to determine the adjuster motor positions when storing or recalling memory seat position settings.
Conditions for Running the DTC
The system voltage must be between 9.0 and 16.0 volts.
Conditions for Setting the DTC
| • | The memory seat module does not detect position sensor movement during adjuster motor operation. |
| • | The motor control circuit monitored by the memory seat module is determined to be shorted to ground, battery positive voltage, or open. |
Action Taken When the DTC Sets
| • | The memory recall functions for the seat motor with a current status DTC will be disabled . |
| • | When the fault is no longer present a history status DTC will be stored, and motor operation will be restored. |
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. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step determines if the DTC is set as the result of an adjuster motor fault or a position sensor fault.
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During this test the memory seat module must see an active switch input before power will be supplied the position sensor.
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During this test the memory seat module must see an active switch input before power will be supplied the position sensor.
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During this test the memory seat module must see an active switch input before power will be supplied the position sensor.
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Power Seats Schematics | |||||||||
1 | Did you perform the Power Seat Diagnostic System Check? | Go to Step 2 | |||||||
2 | Verify the fault is present. Does the system operate normally? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 | ||||||
Attempt to operate the power seat function for which the DTC has set. Is the seat adjuster motor for which the DTC has set inoperative? | Go to Step 4 | Go to Step 6 | |||||||
4 |
Does the test lamp illuminate when the switch is activated and turn off when the switch is released? | Go to Step 12 | Go to Step 5 | ||||||
5 | Test the adjuster motor control circuits for the following conditions:
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 | ||||||
Does the DMM display 5 volts when the adjuster switch is pressed? | Go to Step 7 | Go to Step 9 | |||||||
Does the DMM display 5 volts when the adjuster switch is pressed? | Go to Step 8 | Go to Step 10 | |||||||
Does the DMM display 5 volts when the adjuster switch is pressed? | Go to Step 12 | Go to Step 11 | |||||||
9 | Test the position sensor 5-volt reference circuit for the following conditions:
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 | ||||||
10 | Test the position sensor low reference circuit for an open or short to voltage. 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 | Test the position sensor signal circuit for the following conditions:
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 | ||||||
12 | Inspect for poor connections at the adjuster motor connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 14 | ||||||
13 | Inspect for poor connections at the harness connector of the memory seat module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 15 | ||||||
14 | Replace the appropriate adjuster motor assembly. Refer to Front Seat Adjuster Motor Replacement . Did you complete the replacement? | Go to Step 16 | -- | ||||||
15 | Replace the memory seat module. Refer to Memory Seat Control Module Replacement . Did you complete the replacement? | Go to Step 16 | -- | ||||||
16 |
Does the DTC reset? | Go to Step 3 | System OK | ||||||
