Circuit Description
When you first turn the ignition switch ON, the GAUGES fuse applies Ignition 1 voltage to the Redundant Indicator Ignition 1, terminal B2, and to the AIR BAG warning lamp which is connected to SIR Indicator terminal B1. The AIR BAG fuse applies system voltage to the Ignition 1 input terminals A9 and A10. The inflatable restraint Diagnostic Energy Reserve Module (DERM) then flashes the AIR BAG warning lamp seven times. If Ignition 1 is outside of the normal operating voltage range, the AIR BAG warning lamp will come on solid with no DTCs set.
During engine cranking, the CRANK fuse applies Ignition 1 voltage to the DERM at the Crank input. The DERM then grounds the SIR Indicator output until Ignition 1 voltage is removed from the Crank input. The AIR BAG warning lamp being then comes on during cranking.
After cranking, the DERM flashes the AIR BAG warning lamp six times.
Test Description
Refer to step numbers on the diagnostic table.
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Start at the SIR Diagnostic System Check for all diagnosis.
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This test determines whether the malfunction is in the DERM circuitry or in the instrument cluster power feed circuitry.
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This test checks for an open in the SIR Indicator circuit, instrument cluster circuitry, and AIR BAG warning lamp bulb.
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This test determines whether the malfunction is a short from the SIR Indicator circuit to B+.
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This test checks for an open condition due to a bad bulb.
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This test determines whether the malfunction is an open in the SIR Indicator circuit or an open in the instrument cluster.
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This test determines where the open in circuit 358 is located.
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This test will determine if the blown fuse was the result of fatigue or a circuit short.
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This test determines whether the short-to-ground is due to a short in the wiring or a malfunctioning DERM.
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This test checks for malfunctions due to the following conditions:
| • | An open power feed circuit from the GAUGES fuse to the instrument cluster. |
| • | An open power feed to the GAUGES fuse. |
When measurements are requested in this chart useJ 39200 Digital Multimeter with correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections in Section 8A4. When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair.
Step | Action | Value | Yes | No |
|---|---|---|---|---|
Was the SIR Diagnostic System Check performed? | -- | |||
Does the BRAKE warning lamp come on? | -- | |||
3 |
Is the DERM electrical harness connector damaged or corroded? | -- | ||
4 | Repair the DERM electrical harness connector. Has the connector been repaired? | -- | -- | |
5 | Check for proper connection to the DERM at terminal B1. Are the DERM terminals damaged or corroded? | -- | ||
6 | Check for proper connection to the DERM at terminal B1. Are the DERM terminals damaged and corroded | -- | ||
7 | Replace the DERM. Refer to Inflatable Restraint Diagnostic Energy Reserve Module . Has the DERM been replaced? | -- | -- | |
Measure the resistance on the DERM electrical harness connector from terminal B2 to terminal B1. Is the measurement within the value specified? | 5-25 ohms | |||
Is the voltage less than the value specified? | 1.0 V | |||
10 | Install the instrument cluster. Has the instrument cluster been installed? | -- | Go to Integrity Check | -- |
11 | Repair the short form circuit to 358 to B+. Has the short circuit been repaired? | -- | -- | |
12 |
Is the instrument cluster electrical harness connector damaged or corroded? | -- | ||
13 | Repair the instrument cluster harness electrical connector. Has the connector been repaired? | -- | -- | |
14 | Check for proper connection to the instrument cluster at terminal 6 Are the instrument cluster terminals damaged or corroded? | -- | ||
15 |
Has the instrument cluster been installed? | -- | -- | |
Is the bulb good? | -- | |||
17 |
Has the instrument cluster been installed? | -- | -- | |
Is the resistance less than the value specified? | 5 ohms | |||
19 |
Has the instrument cluster been installed? | -- | -- | |
20 |
Is the connector damaged or corroded? | -- | ||
21 | Repair the electrical C203 terminal D7. Has the short circuit been repaired? | -- | -- | |
Measure the resistance of circuit 358 from electrical connector C203 terminal D7 to the DERM electrical harness connector terminal B1. Is the resistance less than the specified value? | 5 ohms | |||
23 | Repair the open in circuit 358 from C203 to I/P. Has the open circuit been repaired? | -- | -- | |
24 | Repair the open in circuit 358 from C203 to Derm. Has the open circuit been repaired? | -- | -- | |
25 |
Is the fuse good? | -- | ||
Is the fuse good? | -- | |||
27 | Install the GAUGES fuse. Has the fuse been installed? | -- | -- | |
Is the fuse good? | -- | Go to Integrity Check | ||
29 | Repair the short-to-ground in circuit 39 or the instrument cluster. Has the short circuit been repaired? | -- | -- | |
30 |
Is the instrument cluster electrical harness connector damaged or corroded? | -- | ||
31 | Repair the instrument cluster electrical harness connector. Has the connector been repaired? | -- | -- | |
32 | Check for proper connection to the instrument cluster at terminal 28. Are the instrument cluster terminals damaged or corroded? | -- | ||
33 |
Has the instrument cluster been installed? | -- | -- | |
Measure the resistance from instrument cluster electrical harness connector terminal 28 to each terminal of the GAUGES fuse fuseholder. Is either measure less than the value specified? | 5 ohms | |||
35 | Repair the open in circuit 39 between the instrument cluster and the GAUGES fuse fuseholder. Has the open circuit been repaired? | -- | -- | |
36 | Repair the open in power feed to the GAUGES fuse. Has the open circuit been repaired? | -- | -- | |
37 |
Have all the SIR system components been reconnected and properly mounted? | -- | -- | |
38 | Clear all the SIR Diagnostic Trouble Codes. Have the SIR Diagnostic Trouble Codes been cleared? | -- | -- |
