2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 229

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 229

Circuit/System Description

The inflatable restraint front end sensor utilizes a unidirectional 2-wire circuit. The front end sensor modulates current on the interface to send ID,

state of health, and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and

a ground for the front end sensor. When the ignition is turned ON and input power from the SDM is first detected, the front end sensor responds by

performing internal diagnostics and sending an ID to the SDM. The SDM considers the ID to be valid if the response time is less than 5 seconds.

The front end sensor continually communicates status messages to the SDM, which determines if a fault is present in the front end sensor circuit.

When a fault is detected, the SDM may reset the front end sensor up to 2 times by removing and reapplying power to it. If the fault is still present,

the SDM will set a DTC.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

Any of the following conditions exist for 2.5 seconds:

B0083 00, B0084 00, B0085 00, B0086 00, B0087 00, B0088 00

* The front end sensor has been shorted to voltage, open, or shorted to ground.

* The front end sensor current has been above 23 mA for longer than 5 milliseconds.

* The SDM has not received a message from the front end sensor for more than 375 milliseconds.

B0083 0F, B0084 0F, B0085 0F, B0086 0F, B0087 0F, B0088 0F

The SDM has received erratic messages from the front end sensor.

B0083 39, B0084 39, B0085 39, B0086 39, B0087 39, B0088 39

* The SDM has received a Not Ok (NOK) message from the front end sensor.

* The SDM has not received a message.

* The SDM has received invalid serial data from the front end sensor.

B0083 3A, B0084 3A, B0085 3A, B0086 3A, B0087 3A, B0088 3A

* The SDM has received an ID message from the front end sensor, which does not match the ID stored in the SDM memory.

* The SDM has reset the front end sensor twice without detecting the correct ID message.

B0083 71, B0084 71, B0085 71, B0086 71, B0087 71, B0088 71

The SDM has received invalid serial data from the front end sensor.

Action Taken When the DTC Sets

* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.

* The SIR System is disabled and no deployments are allowed.

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.