For 1990-2009 cars
SIR Components
Cell 47
SIR Handling Caution
Handling ESD Sensitive Parts Notice
SIR Schematic Icons
SIR Schematic Icons
SIR Schematic Icons

### Circuit Description

When you first turn the ignition switch to the RUN position, the inflatable restraint sensing and diagnostic module (SDM) performs tests in order to diagnose critical malfunctions within itself. Next the SDM measures Ignition Positive Voltage and the deployment loop voltages in order to ensure they are within the normal voltage ranges. Then the SDM proceeds with the Resistance Measurement test. During one portion of the Resistance Measurement test, the SDM performs the following actions:

• | Grounds the Passenger Low terminal 4 through an internal current sink

• | Connects the Passenger High terminal 1 to an internal constant current source. This current produces proportional voltage drops in the deployment loop.

• | Measures the voltage difference between Passenger High and Passenger Low

• | Calculates the resistance of the passenger deployment loop using the measured voltage

### Conditions for Setting the DTC

• | The driver and passenger deployment loops are not open.

• | The driver and passenger deployment loops are not shorted to voltage.

• | The passenger deployment loop is not shorted to ground.

• | The passenger deployment loop resistance is less than 1.4 ohms. The passenger deployment loop consists of the following components:

- | An inflatable restraint IP module

- | Harness wiring of CKT 1403 (WHT/BLK)

- | Harness wiring of CKT 1404 (DK GRN/WHT)

- | Connector terminal contact

The Resistance Measurement test checks for this malfunction. This test only occurs once each ignition cycle when Ignition Positive Voltage is within the normal operating voltage range.

### Action Taken When the DTC Sets

• | The SDM sets a diagnostic trouble code.

• | The SDM turns ON the AIR BAG warning lamp.

### Conditions for Clearing the MIL/DTC

• | Current DTC

| The resistance of the passenger deployment loop is more than 1.4 ohms and the ignition switch is cycled.

• | History DTC

- | You issue a scan tool Clear DTCs command.

- | 250 ignition cycles have passed since the last malfunction.

When you issue a scan tool Clear DTCs command and the malfunction is still present, the DTC will not reappear until the next ignition cycle.

### Diagnostic Aids

The following condition may cause an intermittent condition:

• | A short circuit between CKT 1403 (WHT/BLK) and CKT 347 (WHT)

• | A short circuit between CKT 1403 (WHT/BLK) and CKT 348 (DK GRN)

• | A short circuit between CKT 1403 (WHT/BLK) and CKT 1404 (DK GRN/WHT)

• | A malfunctioning shorting bar on the inflatable restraint IP module connector

When measurements are requested in this table, use the J 39200 Digital Multimeter with the correct terminal adapter from the J 35616 Connector Test Adapter Kit. When an inspection for proper connection is requested, refer to Intermittents and Poor Connections Diagnosis . When a wire, connector or terminal repair is requested, use the J-38125 Terminal Repair Kit. Refer to Wiring Repair .

The diagnostic table directs the technician to note the entry value of Passenger Resistance. Comparing the value of Passenger Resistance over multiple ignition cycles may be helpful in determining if an intermittent condition exists.

### Test Description

The numbers below refer to the step numbers on the diagnostic table:

1. This test determines the deployment loop resistance measured by the inflatable restraint sensing and diagnostic module (SDM).

2. This test isolates the malfunction to one side of the inflatable restraint IP module yellow 2-way connector.

3. This test checks for proper contact or corrosion of the inflatable restraint IP module connector.

4. This test checks for a short from CKT 1403 (WHT/BLK) to CKT 1404 (DK GRN/WHT).

5. This test checks for a short from CKT 1403 (WHT/BLK) to CKT 348 (DK GRN/WHT).

#### DTC B1016 Passenger Deployment Loop Resistance Low

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the SIR Diagnostic System Check performed? | -- | Go to Step 2 | Go to SIR Diagnostic System Check
2 |

1. Turn the ignition switch to the OFF position.
2. Connect a scan tool to the DLC.
3. Turn the ignition switch to the RUN position.
4. Request the SIR data list display.
5. Read and record on the repair order the passenger deployment loop resistance Passenger Resistance.
6. Request the SIR DTC display.

Is DTC B1022 also present?

--

Go to Step 3

Go to Step 4

3 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint steering wheel and IP module yellow 2-way connectors at the base of the steering column and above the RH sound insulator.
3. Repair the short from CKT 347 (WHT) to CKT 1403 (WHT/BLK). Refer to Wiring Repairs in Wiring Systems.

Are the repairs complete?

--

Go to Step 12

--

4 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint IP module yellow 2-way connector located above the RH sound insulator.
3. Reconnect the 2-way connector.
4. Make sure that the CPA is properly installed.
5. Turn the ignition switch to the RUN position.
6. Using a scan tool, request the SIR data list display.
7. Read the passenger deployment loop resistance Passenger Resistance.

Is Passenger Resistance less than the specified value?

1.4 ohms

Go to Step 6

Go to Step 5

5 |

1. Turn the ignition switch to the OFF position.
2. Replace the inflatable restraint IP module yellow 2-way harness connector. Refer to Wiring Repair .

Are the repairs complete?

--

Go to Step 12

--

6 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint steering wheel and IP module yellow 2-way connectors at the base of the steering column and above the RH sound insulator.
3. Connect J 38715-A SIR Driver/Passenger Load Tool to the harness connectors.
4. Turn the ignition switch to the RUN position.
5. Using the scan tool, request the SIR data list display.
6. Read the passenger deployment loop resistance Passenger Resistance.

Is Passenger Resistance less than the specified value?

1.4 ohms

Go to Step 8

Go to Step 7

7 |

1. Turn the ignition switch to the OFF position.
2. Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement .

Has the inflatable restraint IP module been replaced?

--

Go to Step 12

--

8 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint sensing and diagnostic module (SDM).
3. Disconnect J 38715-A .
4. Measure the resistance from the SDM harness connector terminal 1 to terminal 4.

Is the resistance less than the specified value?

OL

Go to Step 9

Go to Step 10

9 |

1. Turn the ignition switch to the OFF position.
2. Repair the short from CKT 1403 (WHT/BLK) to CKT 1404 (DK GRN/WHT). Refer to Wiring Repairs in Wiring Systems.

Are the repairs complete?

--

Go to Step 12

--

10 | Measure the resistance from the SDM harness connector terminal 1 to terminal 3. Is the resistance less than the specified value? | OL | Go to Step 11 | Go to Sensing and Diagnostic Module Integrity Check
11 | Repair the short from CKT 1403 (WHT/BLK) to CKT 348 (DK GRN/WHT). Refer to Wiring Repairs in Wiring Systems. Are the repairs complete? | -- | Go to Step 12 | --
12 | Reconnect all the SIR system components, make sure all the components are properly mounted. Have all the SIR components been reconnected and properly mounted? | -- | Go to Step 13 | --
13 | Clear the SIR DTCs. Have all the SIR DTCs been cleared? | -- | Go to SIR Diagnostic System Check | --