2010 Cadillac CTS Sedan AWD V6-3.6L Page 168

2010 Cadillac CTS Sedan AWD V6-3.6L Page 168

Circuit/System Description

The inflatable restraint discriminating sensors utilizes a bidirectional 2-wire circuit. The 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 each of the sensors. When the ignition is turned ON and input power from the SDM is first detected, each 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 sensors continually communicates status messages to the SDM, which determines if a fault is present in the sensor or circuit. When a fault is

detected, the SDM may reset the appropriate 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 V.

Conditions for Setting the DTC

All of the following conditions exist for 2.5 seconds:

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

* The sensor signal circuit is shorted to voltage, shorted to ground, or has an open/high resistance.

* The sensor low reference circuit is open.

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

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

The SDM has received erratic messages from the sensor.

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

* The SDM has received a Not OK (NOK) message from the sensor.

* The SDM has not received a message.

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

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

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

Action Taken When the DTC Sets

* The SDM commands the AIR BAG indicator ON.

* 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.

Reference Information

Schematic Reference

SIR Schematics (See: Diagrams/Electrical Diagrams/Air Bag Systems)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation