DTC B1026 Driver Deployment Loop Open. Chevrolet Metro 2001

For 1990-2009 cars
SIR Components
SIR Schematics
SIR Handling Caution
SIR Handling Caution
SIR Handling Caution
Handling ESD Sensitive Parts Notice

### 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 voltage in order to verify the normal ranges. The SDM proceeds with the Deployment Loop Continuity test. During the Deployment Loop Continuity test, the SDM measures the voltage difference between Driver Side High and the Driver Side Low.

### Conditions for Setting the DTC

• | The voltage difference at the driver high side terminal 9 and at the driver low side terminal 10 is 400 mV or more.

• | The malfunction must be present for at least 500 milliseconds during one of the following tests:

- | If the malfunction is detected in the Deployment Loop Continuity test, the Resistance Measurement test will not be performed.

- | The Continuous Monitoring test.

### 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 voltage difference between the driver high side terminal 9 and the driver low side terminal 10 is less than 400 mV for 500 milliseconds.

• | 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.

### Diagnostic Aids

The following conditions can cause an intermittent:

• | A poor connection at terminal 1 and at terminal 2 of the steering column connector of the inflatable restraint steering wheel module.

• | A poor connection at terminal 1 and at terminal 2 of the upper connector of the inflatable restraint steering wheel module coil.

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 .

### DTC Table Test Description

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

1. This step determines the deployment loop voltage difference that the Sensing and Diagnostic Module (SDM) measures.

2. This step checks for correct contact or for corrosion of the yellow 2-way connector.

3. This step isolates the malfunction to one side of the yellow 2-way connector on the inflatable restraint steering wheel module. This connector is located near the base of the steering column.

4. This step determines whether the malfunction is in the inflatable restraint steering wheel module coil or in the inflatable restraint steering wheel module.

5. This step checks for correct contact or for corrosion of the SDM connector.

6. This step checks for correct contact or for corrosion of the SDM connector.

7. This test determines if the malfunction is in the GRN/RED wire.

8. This test determines if the malfunction is in the GRN wire.

#### DTC B1026 Driver Deployment Loop Open

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 instruction manual of the scan tool.
3. Turn the ignition switch to the ON position.
4. Request the SIR data list display.
5. Read the DRIVER VDIF. Record the value on the repair order.

Have you read the DRIVER VDIF and recorded the value on the repair order?

--

Go to Step 3

--

3

1. Turn the ignition switch to the LOCK position.
2. Disconnect the yellow connectors on the inflatable restraint steering wheel module and on the inflatable restraint IP module. These connectors are located near the base of the steering column and behind the IP compartment.
3. Check for the correct connection at terminal 1 and at terminal 2 on the harness side of the yellow 2-way connector on the inflatable restraint steering wheel module. This connector is located at the base of the steering column.

Are the terminals damaged or corroded?

--

Go to Step 4

Go to Step 6

4 | Replace the yellow 2-way harness connector at the base of the steering column. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair . Have you replaced the yellow 2-way harness connector? | -- | Go to Step 5 | --
5 | Check for a correct connection at the terminal D3 and at terminal D4 on the coil side of the 2-way connector of the inflatable restraint steering wheel module. Are the terminals damaged or corroded? | -- | Go to Step 7 | Go to Step 23
6 | Check for a correct connection at the terminal D3 and at terminal D4 on the coil side of the 2-way connector of the inflatable restraint steering wheel module. Are the terminals damaged or corroded? | -- | Go to Step 7 | Go to Step 8
7 | Replace the inflatable restraint steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement . Have you replaced the inflatable restraint steering wheel module coil? | -- | Go to Step 23 | --

8

1. Reconnect the yellow connectors on the inflatable restraint steering wheel module and on the inflatable restraint IP module.
2. Turn the ignition switch to the ON position.
3. Using the scan tool, request the SIR data list display. Read the DRIVER VDIF.

Is the DRIVER VDIF more than the specified value?

400 mV

Go to Step 10

Go to Step 9

9

1. Turn the ignition switch to the LOCK position.
2. Replace the yellow 2-way harness connector at the base of the steering column. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair .

Have you replaced the yellow 2-way harness connector?

Go to Step 23

--

10

1. Turn the ignition switch to the LOCK position.
2. Disconnect the yellow connectors on the inflatable restraint steering wheel module and on the inflatable restraint IP module. These connectors are located near the base of the steering column and behind the IP compartment.
3. Connect the J 38715-A SIR Driver/Passenger Load Tool to the connector of the inflatable restraint steering wheel module and to the harness connector of the inflatable restraint IP module.
4. Turn the ignition switch to the ON position.
5. Using the scan tool, request the SIR data list display. Read the DRIVER VDIF.

Is the DRIVER VDIF more than the specified value?

400 mV

Go to Step 14

Go to Step 11

11

1. Turn the ignition switch to the LOCK position.
2. Remove the inflatable restraint steering wheel module from the steering wheel. Refer to Inflatable Restraint Steering Wheel Module Replacement .
3. Disconnect the J 38715-A from the 2-way connector at the base of the steering column.
4. Reconnect the 2-way connector at the base of the steering column.
5. Connect the J 38715-A to the inflatable module connector on the steering column.
6. Turn the ignition switch to the ON position.
7. Using the scan tool, request the SIR data list display. Read the DRIVER VDIF.

Is the DRIVER VDIF more than the specified value?

400 mV

Go to Step 13

Go to Step 12

12

1. Turn the ignition switch to the LOCK position.
2. Replace the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .

Have you replaced the inflatable restraint steering wheel module?

--

Go to Step 23

--

13

1. Turn the ignition switch to the LOCK position.
2. Replace the inflatable restraint steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement .

Have you replaced the inflatable restraint steering wheel module Coil?

--

Go to Step 23

--

14

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 a correct connection at terminal 9 and at terminal 10 on the harness side of the SDM connector.

Is the SDM harness connector damaged or corroded?

--

Go to Step 15

Go to Step 17

15 | Replace the SDM harness connector. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair . Have you replaced the SDM harness connector? | -- | Go to Step 16 | --
16 | Check for a correct connection at terminal 9 and 10 on the SDM. Are the SDM terminals damaged or corroded? | -- | Go to Step 18 | Go to Step 23
17 | Check for a correct connection at terminal 9 and at terminal 10 on the SDM. Are the SDM terminals damaged or corroded? | -- | Go to Step 18 | Go to Step 19
18 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Have you replaced the SDM? | -- | Go to Step 23 | --

19

1. Zero the J 39200 .
2. Measure the resistance from the SDM harness connector terminal 9 to terminal 2 of the 2-way harness connector of the inflatable restraint steering wheel module.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Step 21

Go to Step 20

20 | Repair the high resistance in the GRN/RED wire. Have you repaired the circuit? | -- | Go to Step 23 | --

21

1. Zero the J 39200 .
2. Measure the resistance from the SDM harness connector terminal 10 to terminal 1 of the 2-way harness connector of the inflatable restraint steering wheel module.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to AIR BAG Warning Lamp Comes On Steady

Go to Step 22

22 | Repair the high resistance in the GRN wire. Have you repaired the circuit? | -- | Go to Step 23 | --
23 | Reconnect and mount all of the SIR system components. Have you reconnected and correctly mounted all the SIR components? | -- | Go to Step 24 | --
24 | Clear the SIR diagnostic trouble codes. Have you cleared the SIR Diagnostic trouble codes? | -- | Go to SIR Diagnostic System Check | --