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

### Circuit Description

When you first turn the ignition switch to the ON position, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within itself. The SDM monitors the voltages at PASSENGER SEAT LOW terminal 1 to detect a short to ground in the inflator module circuit.

### Conditions for Setting the DTC

The SDM detects a short to ground in the RH front seat deployment loop.

### Action Taken When the DTC Sets

• | The SDM sets a Diagnostic Trouble Code.

• | The SDM flashes the AIR BAG warning lamp.

### Conditions for Clearing the DTC

All DTCs are cleared with each ignition cycle.

### Diagnostic Aids

A short to ground in the inflatable restraint passenger seat module circuit can cause an intermittent condition. Inspect the YEL/RED and YEL/GRN wires leading to the seat module carefully for cut or chafed wires.

### Test Description

1. This test checks for a short to ground in the inflatable restraint passenger seat module high circuit.

2. This test checks for a short to ground in the inflatable restraint passenger seat module low circuit.

3. This test determines if the malfunction is caused by the SDM.

4. This test determines if the malfunction is caused by the inflatable restraint passenger seat module.

Step | Action | Value(s) | 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 OFF position.
2. Disconnect the inflatable restraint Sensing and Diagnostic Module (SDM).
3. Disconnect the inflatable restraint passenger seat module.
4. Measure the resistance at the seat module harness connector between terminal 1 and ground.

Is the resistance measured equal to the specified value?

OL

(Infinite)

Go to Step 3

Go to Step 8

3 | Measure the resistance at the seat module connector between terminal 2 and ground. Is the resistance measured equal to the specified value? | OL (Infinite) | Go to Step 4 | Go to Step 8
4 |

1. Connect the SDM.
2. Connect a jumper wire between terminals 1 and 2 of the seat module connector.
3. Turn the ignition switch to the ACC or ON position and wait 20 seconds.
4. Read SIR DTCs

Is DTC 41 present?

--

Go to Step 6

Go to Step 5

5 |

1. Turn the ignition switch to the OFF position.
2. Connect the seat module connector.
3. Turn the ignition switch to ACC or ON and wait 20 seconds.
4. Read SIR DTCs.

Is DTC 41 present?

--

Go to Step 7

Go to Step 9

6 | Replace the inflatable restraint Sensing and Diagnostic Module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Are all the repairs complete? | -- | Go to Step 10 | --
7 | Replace the inflatable restraint passenger seat module. Refer to Inflatable Restraint Seat Module Replacement - Passenger . Are all the repairs complete? | -- | Go to Step 10 | --
8 | Repair the IP wiring harness between the passenger seat module and the SDM. Refer to Wiring Repair . Are all the repairs complete? | -- | Go to Step 10 | --
9 | An intermittent exists in the passenger seat deployment loop. Refer to Diagnostic Aids. Are all the repairs complete? | -- | Go to Step 10 | --
10 | Reconnect all SIR components. Make sure all components are properly mounted. Have all the SIR components been reconnected and properly mounted? | -- | Go to SIR Diagnostic System Check | --