B0091

DTC B0091

Circuit Description

The inflatable restraint instrument panel module (IPM) disable switch circuit consists of an IPM disable switch, IPM disable switch indicator, IPM disable switch signal circuit, and IPM suppression indicator control circuit. When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. The SDM monitors the voltage levels at the IPM disable switch signal and the IPM suppression indicator control circuits of the SDM to determine the position of the IPM disable switch. If a malfunction is detected, a DTC will be stored in memory.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B0091 Active Switch: Wrong State

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Conditions for Setting the DTC

The voltage at IPM disable switch signal is low with the IPM disable switch indicator ON and the voltage at IPM suppression indicator control is high for 500 milliseconds.

Action Taken When the DTC Sets

* The IPM disable switch is defaulted to a calibrated state.
* The SDM commands ON the AIR BAG indicator via class 2 serial data.
* The SDM toggles the IPM disable switch AIR BAG indicator ON and OFF every 5 seconds.

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 IPM disable switch signal and the IPM suppression indicator control circuits. Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Test Description

Step 1 - Step 11:

The numbers below refer to the step numbers on the diagnostic table.
3. This step observes the state of the IPM disable switch, normal state being ON.
4. This step tests for a malfunctioning IPM disable switch.
5. This step tests for a malfunctioning SDM.
6. This step tests for a short in the IPM disable switch signal circuit.
7. This step tests for a short in the IPM suppression indicator control circuit.