GM Service Manual Online
For 1990-2009 cars only

Object Number: 590599  Size: SF
SIR Component Views
Power, Ground, IP MIL, SDM, IP Module, Steering Wheel Coil, STeEring Wheel Module, Seat Belt Switch and Seat Belt/Ignition Key/Lamps Alarm
SIR Handling Caution
Handling ESD Sensitive Parts Notice

Circuit Description

When you first turn ON the ignition, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. Next the SDM measures IGNITION 1 and the deployment loop voltages to make sure they are within their respective normal voltage ranges. Then the SDM proceeds with the resistance measurement test. During one portion of the resistance measurement test, the SDM does the following:

    • Grounds the passenger side low circuit through an internal circuit sink.
    • Connects the passenger side high circuit to an internal constant current source. This current produces proportional voltage drops in the deployment loop.
    • Measures the voltage difference between the passenger side high circuit and the passenger side low circuit.
    • Calculates the resistance of the passenger deployment loop using the measured voltage.

Conditions for Running 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.

Conditions for Setting the DTC

The passenger deployment loop resistance is less than 1.4 ohms.

The resistance measurement test checks for this malfunction. This test occurs once each ignition cycle when IGNITION 1 is within the normal operating voltage range.

Action Taken When the DTC Sets

The SDM commands ON the AIR BAG warning lamp.

Conditions for Clearing the DTC

    • The passenger deployment loop resistance is less than 1.4 ohms.
    • You can issue a CLEAR CODES 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 passenger side high circuit and the driver side high circuit.
    • A short between the passenger side high circuit and the driver side low circuit.
    • A short between the passenger side high circuit and the passenger side low circuit.
    • A malfunctioning shorting bar on the inflatable restraint IP module connector.

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

When measurements are requested in this table, use the J 39200 DMM with the correct terminal adapter from the J 35616 Connector Test Adapter Kit. When an inspection for proper connection is requested, refer to Testing for Electrical Intermittents in Wiring Systems. When a wire, connector or terminal repair is requested, use the J-38125 Terminal Repair Kit and refer to Wiring Repairs in Wiring Systems.

Test Description

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

  1. This step checks the passenger deployment loop resistance that was measured by the inflatable restraint sensing and diagnostic module (SDM).

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

  3. This step checks to see if there is a short between the passenger side high circuit and the passenger side low circuit.

  4. This step checks to see if there is a short between the passenger side high circuit and the driver side low circuit.

DTC B1016 Passenger Deployment Loop Resistance Low

Step

Action

Value(s)

Yes

No

1

Did you perform the SIR Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - SIR

2

  1. Turn OFF the ignition.
  2. Install the scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Use the scan tool to request the SIR scan tool data list.
  5. Read and record on the repair order the passenger deployment loop resistance PASSENGER RESISTANCE.
  6. Use the scan tool to request the SIR DTC display.

Is DTC B1022 also present?

--

Go to Step 3

Go to Step 4

3

  1. Turn OFF the ignition.
  2. Disconnect the inflatable restraint steering wheel module coil and IP module yellow 2-way wiring harness connectors.
  3. Locate a short between the driver side high circuit and the passenger side high circuit.
  4. Repair the short between the driver side high circuit and the passenger side high circuit.

Did you complete the repair?

--

Go to Step 13

--

4

  1. Turn OFF the ignition.
  2. Disconnect the inflatable restraint IP module yellow 2-way wiring harness connector.
  3. Reconnect the inflatable restraint IP module yellow 2-way wiring harness connector.
  4. Verify that the CPA is properly installed.
  5. Turn ON the ignition, with the engine OFF.
  6. Use the scan tool to request the SIR scan tool data list.
  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 OFF the ignition.
  2. Replace the inflatable restraint IP module yellow 2-way wiring harness connector. Refer to Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 13

--

6

  1. Turn OFF the ignition.
  2. Disconnect the inflatable restraint steering wheel module coil and IP module yellow 2-way wiring harness connectors.
  3. Install the J 38715-A SIR Driver/Passenger Load Tool PASSENGER INFLATOR connector to inline connector C216 and BASE OF COLUMN connector to inline connector C215.
  4. Turn ON the ignition, with the engine OFF.
  5. Use the scan tool to request the scan tool data list.
  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 OFF the ignition.
  2. Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement .

Did you complete the repair?

--

Go to Step 13

--

8

  1. Turn OFF the ignition.
  2. Disconnect the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  3. Remove the J 38715-A .
  4. Use the J 39200 Digital Multimeter to measure the resistance between the passenger side high circuit and the passenger side low circuit of the SDM wiring harness connector.

Is the measured resistance less than the specified value?

OL

Go to Step 9

Go to Step 10

9

Locate a short between the passenger side high circuit and the passenger side low circuit.

Did you complete the repair?

--

Go to Step 13

--

10

Use the J 39200 to measure the resistance between the passenger side high circuit and the driver side low circuit of the SDM wiring harness connector.

Is the measured resistance less than the specified value?

OL

Go to Step 12

Go to Step 11

11

Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Did you complete the repair?

--

Go to Step 13

--

12

  1. Locate a short between the passenger side high circuit and the driver side low circuit.
  2. Repair the short between the passenger side high circuit and the driver side low circuit.

Did you complete the repair?

--

Go to Step 13

--

13

  1. Reconnect all SIR components.
  2. Verify that all components and connectors are properly mounted.
  3. Turn On the ignition, with the engine OFF.
  4. Use the scan tool in order to clear the DTCs.

Did you complete the action?

--

Go to Diagnostic System Check - SIR

--