Circuit Description
The data link connector (DLC) is the provision for communicating with the inflatable restraint sensing and diagnostic module (SDM). The DLC is located under the instrument panel. The DLC supplies Battery voltage and ground to the scan tool. The scan tool communicates with the SDM on the serial data line. The scan tool is connected to the DLC in order to perform the following functions:
| • | Read the data list |
| • | Read diagnostic trouble codes (DTCs) |
| • | Clear DTCs |
When measurements are requested in this table, use J 39200 Digital Multimeter with the correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to General Electrical Diagnosis in Wiring Systems. When a wire, connector or terminal repair is requested, use 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.
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This test checks for an open or high resistance condition in the SDM ground circuit.
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This test checks for an open or high resistance condition in the SDM voltage feed circuit.
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This test checks for an open or high resistance condition in the serial data circuit.
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This test checks for a short to ground condition in the serial data circuit.
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This test checks for a short to voltage condition in the serial data circuit.
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This test checks for a short to ground condition in the SDM voltage feed circuit.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Data Link Connector Schematics and SIR Schematics in SIR | ||||
1 | Did you perform the SIR Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Is the fuse open? | -- | Go to Step 3 | Go to Step 8 |
Is the resistance within the specified range? | 0-2 ohms | Go to Step 4 | Go to Step 11 | |
Is the voltage within the specified range? | Battery Voltage | Go to Step 5 | Go to Step 12 | |
Is the resistance within the specified range? | 0-2 ohms | Go to Step 6 | Go to Step 13 | |
With the ignition switch in the OFF position, connect a J 39200 between terminal 7 of the DLC and ground in order to measure the resistance. Is the resistance within the specified range? | OL | Go to Step 7 | Go to Step 14 | |
Is the voltage within the specified range? | 0-1 V | Go to Step 16 | Go to Step 15 | |
Is the resistance within the specified range? | OL | Go to Step 9 | Go to Step 10 | |
9 |
Are the repairs complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
10 |
Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
11 | Repair the open or high resistance condition in the SDM ground circuit. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
12 | Repair the open or high resistance condition in the ignition voltage feed circuit between the SDM and the Ignition Switch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
13 | Repair the open or high resistance condition in the serial data circuit - pin A4 - between the SDM and the DLC. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
14 | Repair the short to ground in the serial data circuit - pin A4 - between the SDM and the DLC. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
15 | Repair the short to voltage in the serial data circuit - pin A4 - between the SDM and the DLC. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
16 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Is the repair complete? | -- | Go to Diagnostic System Check - SIR in SIR | -- |
