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B0084



DTC B0083 or B0084

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B0083
- Right Front/Passenger Seat Position Sensor Circuit

DTC B0084
- Left Front/Driver Seat Position Sensor Circuit

Diagnostic Fault Information






Circuit/System Description

The inflatable restraint seat position sensor (SPS) is used to determine the proximity of a front driver or passenger seat position with respect to the frontal air bag. The SPS interfaces with the sensing and diagnostic module (SDM). The state of the SPS allows the SDM to disable stage 2 of the frontal air bag for a front seat that is forward of a forward/rearward point in seat track travel. The SPS is a hall effect sensor that is mounted near the seat track of both the driver and passenger seats. The seat track includes a metal bracket that shunts the SPS magnetic circuit creating 2 states of seat position. The shunted state represents a rearward seat position. The non-shunted state represents a forward position. The SPS provides 2 current ranges, one range for the shunted state and a second range for a non-shunted state. These 2 states are inputs to the SDM. State 1 (shunted) being the rearward threshold and state 2 (non-shunted) being the forward threshold. When the SDM receives input from a SPS that state 1 threshold is reached (seat is rearward) the SDM will not disable stage 2 deployment, if required by the deployment sensors. When state 2 threshold is reached (seat is forward) the SDM will disable stage 2 deployment on the side the seat is forward. The SDM monitors the SPS circuit and if a fault is detected the SDM will set codes B0083 or B0084 and defaults to disabling stage 2 frontal deployment. This will only default on the side of the vehicle the sensor has a fault. Its important to understand that the SPS is secondary to the passenger presence system (PPS) and the manual instrument panel (I/P) module disable switch. If either one of these devices are in the disable mode the passenger air bag will not deploy regardless of the SPS status.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

* The SDM detects the SPS circuit amperage is 4 mA or less for 500 milliseconds.
* The SDM detects the SPS circuit amperage is 18 mA or greater for 500 milliseconds.

Action Taken When the DTC Sets

* The SDM commands the AIR BAG indicator ON.
* The SDM defaults to disabling stage 2 frontal deployment.

Conditions for Clearing the DTC

* The condition for setting the DTC no longer exists.
* A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Circuit/System Verification

Ignition ON, observe the scan tool Driver Seat Position Sensor parameter and Passenger Seat Position Sensor parameter while commanding the appropriate seat BACKWARD and FORWARD, the reading should change between Rearward and Forward.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate inflatable restraint seat position sensor.
2. Disconnect the harness connector at the SDM.
3. Ignition ON, test for less than 1-volt between the appropriate inflatable restraint seat position sensor circuit terminal B and ground.

^ If greater than the specified range, test the circuit for a short to voltage.

4. Test for less than 1-volt between the appropriate inflatable restraint seat position sensor circuit terminal A and ground.

^ If greater than the specified range, test the circuit for a short to voltage.

5. Ignition OFF, test for infinite resistance between the appropriate inflatable restraint seat position sensor circuit terminal B and ground.

^ If less than the specified range, test the signal circuit for a short to ground.

6. Test for less then 1 ohm between the following inflatable restraint seat position sensor circuit terminals:

* Right front end sensor terminal B and SDM harness connector terminal 28.
* Left front end sensor terminal B and SDM harness connector terminal 28.

^ If greater than the specified range, test the circuit for an open/high resistance.

7. Test for less then 1 ohm between the following inflatable restraint seat position sensor circuit terminals:

* Right front end sensor terminal A and SDM harness connector terminal 30.
* Left front end sensor terminal A and SDM harness connector terminal 29.

^ If greater than the specified range, test the circuit for an open/high resistance.

8. If all circuits test normal, replace the appropriate inflatable restraint seat position sensor.
9. Reconnect the harness connector at the SDM and appropriate inflatable restraint seat position sensor.
10. Ignition ON, with a scan tool clear and recheck for DTCs.

^ If the seat position sensor DTC resets and is current, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Inflatable Restraint Seat Position Sensor Replacement
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