B0083

DTC B0083

CIRCUIT 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 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 on the seat track of both the driver and passenger seats. The seat track includes a metal bracket that shunts the SPS magnetic circuit creating two states of seat position. The shunted state represents a rearward seat position. The non-shunted state represents a forward position. The SPS provides two current ranges, one range for the shunted state and a second range for a non-shunted state. These two states are inputs to the sensing and diagnostic module (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. It's important to understand that the SPS is secondary to the passenger presence system (PPS) and the manual 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 1 voltage is within the normal operating voltage range.

CONDITIONS FOR SETTING THE DTC
DTC B0083 and B0084 will set when one of the following conditions occur:
- The SDM detects the SPS circuit amperage is 4 mA or less for 500 milliseconds.
- The SDM detects the SPS circuit amperage is between 8 mA and 11 mA 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 via Class 2 serial data.
- The SDM defaults the SPS to seat forward threshold.

CONDITIONS FOR CLEARING THE DTC
- The condition responsible for setting the DTC no longer exists.
- You issue a scan tool CLEAR DTCs command.
- A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DIAGNOSTIC AIDS
The following can cause an intermittent condition:
- A short between the SPS signal and low reference circuits
- High or low resistance in the SPS signal and low reference circuits
- Inspect the SPS signal and return circuits carefully for cutting and/or chafing

TEST DESCRIPTION

Steps 1-3:

Steps 4-6:

Steps 7-10:

Steps 11-12:

The numbers below refer to the step numbers on the diagnostic table:
2. Inspects the SPS connector and terminals.
6. Tests for a short to ground, a high resistance, or an open in the SPS signal circuit.
7. Tests for a short to ground, a high resistance, or an open in the SPS low reference circuit.
8. Tests for a short to voltage in the SPS signal and low reference circuits.