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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Metro 🢒 Restraints 🢒 SIR 🢒 DTC B1015 Passenger Deploy. Loop Resistance High

Object Number: 420290 Size: SF
SIR Components
SIR Schematics
SIR Handling Caution
Handling ESD Sensitive Parts Notice
SIR Handling Caution

Circuit Description

When you turn the ignition switch to the ON position, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests in order to diagnose critical malfunctions. Next, the SDM measures IGNITION 1 and the deployment loop voltages in order to verify the normal ranges. The SDM proceeds with the Resistance Measurement test. During one portion of the Resistance Measurement test, the SDM performs the following functions:

    • Grounds the passenger side low circuit at terminal 3
    • Connects the Passenger Side High terminal 4 to an internal constant current source. This current produces proportional voltage drops in the deployment loop.
    • Measures the voltage difference between Passenger Side High and Passenger Side Low.
    • Calculates the resistance of the passenger deployment loop using the measured voltage.

Conditions for Setting the DTC
    • The driver deployment loop and the passenger deployment loop are not open.
    • The driver deployment loop and the passenger deployment loop are not shorted to voltage.
    • The passenger deployment loop does not have a short to ground.
    • The passenger deployment loop resistance is more than 3.0 ohms. The passenger deployment loop consists of the following components:
       - The inflatable restraint IP module.
       - The harness wiring of the YEL/RED wire.
       - The harness wiring of the YEL wire.
       - The connector terminal contact.

The Resistance Measurement test checks for this malfunction. This test only occurs once each ignition cycle if IGNITION 1 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 DTC
    • Clear the Current DTC if the resistance of the passenger deployment loop is less than 3.0 ohms and the ignition switch is cycled.
    • Clear the History DTC under the following conditions:
       - Use a scan tool in order to clear the DTC.
       - 250 malfunction-free ignition cycles have occurred.

If you use a scan tool in order to clear the DTC, and the malfunction is still present, the DTC will not appear until the next ignition cycle.

Diagnostic Aids

A poor connection can cause an intermittent condition. Check the following circuits for a poor connection:

    • Terminal 1 and terminal 2 of the harness connector of the inflatable restraint IP module
    • Terminal 4 and terminal 3 of the SDM
    • The wire to terminal connections in the YEL/RED wire.
    • The wire terminal connections in the YEL wire.

If this table requests measurements, use the J 39200 Digital Multimeter with the correct terminal adapter from the J 35616 Connector Test Adapter Kit. If a check for a correct connection is requested, refer to Testing for Intermittent Conditions and Poor Connections . If a wire repair, a connector repair, or a terminal repair is requested, use the J-38125 Terminal Repair Kit, and refer to Wiring Repair .

Test Description

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

  1. This test determines the deployment loop resistance that the Sensing and Diagnostic Module (SDM) measured.

    2.

  2. This test checks for correct contact and/or for corrosion of the yellow connector.

    3.

  3. This test isolates the malfunction to one side of the yellow connector of the inflatable restraint IP module. This is done by substituting the known good resistance of the load tool, then observing if the malfunction is still present.

    4.

  4. This test checks for correct contact and/or for corrosion of the SDM connector.

    5.

  5. This test determines if the malfunction is in the YEL/RED wire.

    6.

  6. This test determines if the malfunction is in the YEL wire.

DTC B1015 Passenger Deploy Loop Resistance High

Step

Action

Values

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 LOCK position.
  2. Connect a scan tool to the data link connector. Follow the directions in the scan tool instruction manual.
  3. Turn the ignition switch to the ON position.
  4. Request the SIR data list display.
  5. Read and record PASSENGER RESISTANCE on the repair order.

Did you record PASSENGER RESISTANCE on the repair order?

--

Go to Step 3

--

3

  1. Turn the ignition switch to the LOCK position.
  2. Disconnect the yellow connectors of the inflatable restraint steering wheel module and of the inflatable restraint IP module. The connectors are under the steering wheel side cap and behind the IP compartment.
  3. Check for poor contact at terminal 1 and at terminal 2 on the harness side of the connector of the inflatable restraint IP module.

Are the terminals damaged or corroded?

--

Go to Step 4

Go to Step 6

4

Replace the harness connector of the inflatable restraint IP module.

Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair in this section.

Did you replace the harness connector of the inflatable restraint IP module?

--

Go to Step 5

--

5

Check for the correct connection at terminal 1 and at terminal 2 on the connector of the inflatable restraint IP module.

Are the terminals damaged or corroded?

--

Go to Step 7

Go to Step 21

6

Check for the correct connection at terminal B1 and at terminal B2 on the connector of the inflatable restraint IP module.

Are the terminals damaged or corroded?

--

Go to Step 7

Go to Step 8

7

Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement in this section.

Did you replace the inflatable restraint IP module?

--

Go to Step 21

--

8
  1. Connect the yellow connectors of the inflatable restraint steering wheel module and of the inflatable restraint IP module.
  2. Turn the ignition switch to the ON position.
  3. Using the scan tool, display the SIR data list. Read the PASSENGER RESISTANCE.

Is the PASSENGER RESISTANCE more than the specified value?

3.0 ohms

Go to Step 10

Go to Step 9

9
  1. Turn the ignition switch to the LOCK position.
  2. Replace the harness connector of the inflatable restraint IP module. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair in this section.

Did you replace the harness connector of the inflatable restraint IP module?

--

Go to Step 21

--

10

  1. Turn the ignition switch to the LOCK position.
  2. Disconnect the yellow connectors of the inflatable restraint steering wheel module and of the inflatable restraint IP module.The connectors are under the steering wheel side cap and behind the IP compartment.
  3. Connect the J 38715-A SIR Driver/Passenger Load Tool to harness connectors of the inflatable restraint steering wheel module and of the inflatable restraint IP module.
  4. Turn the ignition switch to the ON position
  5. Using the scan tool, display the SIR data list. Read the PASSENGER RESISTANCE.

Is the PASSENGER RESISTANCE more than the specified value?

3.0 ohms

Go to Step 12

Go to Step 11

11
  1. Turn the ignition switch to the LOCK position.
  2. Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement in this section.

Did you replace the inflatable restraint IP module?

--

Go to Step 21

-

12

  1. Turn the ignition switch to the LOCK position.
  2. Disconnect the Sensing and Diagnostic Module (SDM).
  3. Disconnect the J 38715-A .
  4. Check for the correct connection at terminal 4 and at terminal 3 on the harness side of the SDM connector.

Is the SDM harness connector damaged or corroded?

--

Go to Step 13

Go to Step 15

13

Replace the SDM harness connector. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair in this section.

Did you replace the SDM harness connector?

--

Go to Step 14

--

14

Check for the correct connection at terminal 4 and at terminal 3 on the SDM.

Are the SDM terminals damaged or corroded?

--

Go to Step 16

Go to Step 21

15

Check for the correct connection at terminal 4 and at terminal 3 on the SDM.

Are the SDM terminals damaged or corroded?

--

Go to Step 16

Go to Step 17

16

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

Did you replace the SDM?

--

Go to Step 21

--

17

Zero the J 39200 , and measure the resistance from the SDM harness connector terminal 4 to harness connector terminal 2 of the inflatable restraint IP module.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Step 19

Go to Step 18

18

Repair high resistance in the YEL/RED wire.

Is the circuit repair complete?

--

Go to Step 21

--

19

Zero the J 39200 , and measure the resistance from the SDM harness connector terminal 3 to harness connector terminal 1 of the inflatable restraint IP module.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Step 20

Go to Step 21

20

Reconnect all the SIR system components. Confirm that all the components are correctly mounted.

Are all the SIR components reconnected and correctly mounted?

--

Go to Sensing and Diagnostic Module Integrity Check

--

21

Repair high resistance in the YEL wire.

Is the circuit repair complete?

--

Go to Step 21

--

22

Reconnect all the SIR components. Confirm that all components are correctly mounted.

Are all the SIR components been reconnected and correctly mounted?

--

Go to Step 22

--

23

Clear the SIR diagnostic trouble codes. Did you clear the SIR diagnostic trouble codes?

--

Go to SIR Diagnostic System Check

--