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Supplemental Inflatable Restraint System GMC Savana I

Airbag 17 illustrations ~15860 words

CONNECTOR IDENTIFICATION

Note. Refer to illustrations to identify SIR connector terminals. (Scheme 1)- (Scheme 5).

Scheme 1

Scheme 1: CONNECTOR IDENTIFICATION
Scheme 1: CONNECTOR IDENTIFICATION

Scheme 2

Scheme 2
Scheme 2

Scheme 3

Scheme 3
Scheme 3

Scheme 4

Scheme 4
Scheme 4

Scheme 5

Scheme 5
Scheme 5

DESCRIPTION & OPERATION

WARNINGTo avoid injury from accidental air bag deployment, read and carefully follow all WARNINGS and SERVICE PRECAUTIONS .

SUPPLEMENTAL INFLATABLE RESTRAINT (SIR) SYSTEM

Supplemental Inflatable Restraint (SIR) system is designed to supplement protection provided by driver and passenger-side seat belts. A frontal crash of sufficient force up to 30 degrees off center line of vehicle will deploy driver and passenger-side air bags. Steering column and knee bolsters below instrument panel also absorb crash energy.

SIR system consists of Sensing and Diagnostic Module (SDM), driver and passenger-side air bag modules, front-end discriminating sensor, SIR coil assembly and AIR BAG warning light in instrument cluster.

SENSING & DIAGNOSTIC MODULE (SDM)

SDM monitors vehicle velocity changes to detect frontal crashes which are severe enough to warrant air bag module deployment. When a frontal crash of sufficient force is detected, SDM causes enough current flow through air bag modules to deploy air bags. SDM also maintains a 23 Volt Loop Reserve (23 VLR) energy supply to provide deployment energy for up to 10 minutes after loss of voltage.

Additionally, SDM provides diagnostic monitoring of SIR system electrical components. When a malfunction is detected, SDM sets a Diagnostic Trouble Code (DTC) which can be retrieved using a scan tool. SDM warns driver of system malfunctions by controlling AIR BAG warning light.

AIR BAG WARNING LIGHT

Ignition switch applies battery voltage to AIR BAG warning light. SDM controls light by providing ground with a light driver. When ignition switch is first turned ON, AIR BAG warning light verifies system operation by flashing 7 times and turning off. During vehicle operation, AIR BAG warning light warns driver of malfunctions which could potentially affect SIR system operation.

FRONT-END DISCRIMINATING SENSOR

Front-end discriminating sensor is an auxiliary sensor which assists SDM in determining when deployment should occur by providing an input signal. Although front-end discriminating sensor is mechanical, it is not part of deployment loop.

SIR COIL ASSEMBLY

SIR coil assembly consists of 2 or more current-carrying coils. Coils are attached to steering column and allow rotation of steering wheel, while maintaining continuous (directly wired) contact of deployment loop through driver-side air bag module.

AIR BAG MODULES

Air bag modules consist of an inflatable bag and an inflator. When vehicle is in an accident of sufficient force, SDM causes current flow through deployment loops. Current passing through inflators ignites inflator charges, producing gas which rapidly inflates air bags.

Some vehicles equipped with driver seat only use a trim cover instead of a passenger-side air bag module. Trim cover contains a diagnostic resistor and pigtail harness, to allow SDM to sense proper deployment loop resistance.

KNEE BOLSTERS

Knee bolsters are used to absorb energy and control forward movement of front passengers. This is accomplished by limiting leg movement during a frontal crash.

SERVICE PRECAUTIONS

Note. *** PLEASE READ THIS FIRST ***

Observe the following precautions when working with SIR system

  1. SDM maintains sufficient voltage to cause air bag deployment for up to 10 minutes after ignition switch is turned OFF, battery is disconnected, or fuse powering SDM is removed. In order to begin servicing immediately, inflator modules must be removed from deployment loop. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system) .
  2. After repairs, ensure AIR BAG warning light is working properly and no system faults are indicated. See «SYSTEM OPERATION CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__system-operation-check) .
  3. Always wear safety glasses when servicing or handling an air bag module.
  4. Air bag modules must be stored in original special containers until used for service. Store in a clean, dry place, away from sources of extreme heat, sparks, or high electrical energy.
  5. Air bag modules or SDMs should not be subjected to temperatures greater than 150°F (65°C).
  6. Air bag modules or SDMs should not be used if they have been dropped from a height of 3 feet or greater.
  7. When placing a live air bag module on a bench or other surface, always make certain that trim cover faces up. This will reduce motion of module if accidentally deployed.
  8. After deployment, air bag surface may contain deposits of sodium hydroxide, which can irritate skin. Always wear safety glasses, rubber gloves and long-sleeved shirt during clean-up, and wash hands using mild soap and water. Follow correct disposal procedures. See «DISPOSAL PROCEDURES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disposal-procedures) .
  9. At no time should any electrical source be allowed near inflator on back of air bag module.
  10. DO NOT apply power to SIR system unless all components are connected or a diagnostic chart requests it, as this will set a diagnostic trouble code.
  11. When carrying a live air bag module, trim cover should be pointed away from body to minimize injury in case of accidental deployment.
  12. DO NOT attempt to service SDM, front-end discriminating sensor, SIR coil assembly, or air bag modules. If defective, these parts must be replaced.
  13. DO NOT probe a wire through insulator; this damages wire and eventually causes failure due to corrosion.
  14. When performing electrical tests, prevent accidental shorting of terminals. Such mistakes can damage fuses or components and may cause a second fault code to set, making diagnosis of original problem more difficult.
  15. When using diagnostic charts to diagnose SIR system, under no circumstances should a volt/ohmmeter, test light or any type of electrical equipment not specified by manufacturer be used. See «SPECIAL TOOLS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
  16. If SIR system is not fully functional for any reason, vehicle should not be driven until system is repaired. DO NOT remove bulbs, modules, sensor or other components or in any way disable system from operating normally.

SPECIAL TOOLS

To avoid accidental deployment when working on SIR system, use only electrical test equipment specified by manufacturer. See SIR RECOMMENDED TOOLS table.

Tool NameTool Number
Connector Test Adapter KitJ-35616-A
Digital MultimeterJ-39200
Scan ToolTech 2
SIR Deployment HarnessJ-38826
SIR Driver/Passenger Load ToolJ-38715-A
SIR Shorting Bar ToolJ-38715-96
Steering Wheel PullerJ-1859-A
Steering Wheel Puller LegsJ-36541
Terminal Repair KitJ-38125-B

SIR RECOMMENDED TOOLS

CENTERING COIL ASSEMBLY

  1. If coil assembly has been removed from steering column and is being reinstalled, go to next step. New coil assemblies are pre-centered and include a centering tab that is removed once coil is installed.
  2. Hold coil assembly with clear bottom upward to see coil bottom. While holding coil assembly housing, depress spring lock and rotate hub in direction of arrow until it stops. Coil ribbon should now be wound up snugly against center hub. Rotate coil hub in opposite direction approximately 2 1/2 turns. Release spring lock between locking tabs. (Scheme 6)

Scheme 6

Scheme 6
Scheme 6

DISABLING & ACTIVATING AIR BAG SYSTEM

Note. *** PLEASE READ THIS FIRST ***

CAUTIONWhen battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES in GENERAL INFORMATION. Record preset radio stations and obtain code for theft deterrent-equipped radios before disconnecting battery.

DISABLING SYSTEM

WARNINGSDM maintains sufficient voltage to cause air bag deployment for up to 10 minutes after ignition switch is turned OFF, battery is disconnected, or fuse powering SDM is removed. In order to begin servicing immediately, inflator modules must be removed from deployment loop.

Note. When AIR BAGS fuse is removed and ignition switch is in RUN position, AIR BAG warning light will be on. This does not indicate a system malfunction.

  1. Turn steering wheel to place vehicle wheels in straight-ahead position. Turn ignition switch to LOCK position and remove key.
  2. Remove AIR BAGS fuse (10-amp) from instrument panel fuse block. Remove driver-side knee bolster. Remove Connector Position Assurance (CPA) clip and disconnect driver-side Yellow 2-pin connector at base of steering column. (Scheme 7) Remove passenger-side knee bolster. Remove Connector Position Assurance (CPA) clip and disconnect passenger-side Yellow 2-pin connector located behind passenger-side knee bolster. (Scheme 8)

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8

ACTIVATING SYSTEM

Remove key from ignition switch. Connect passenger-side Yellow 2-pin connector and CPA clip. Install passenger-side knee bolster. Connect driver-side Yellow 2-pin connector and CPA clip. Install driver-side knee bolster. Install AIR BAGS fuse. Check system for proper operation. See SYSTEM OPERATION CHECK .

DISPOSAL PROCEDURES

WARNINGTo prevent accidental deployment and personal injury, deploy air bags before disposal. DO NOT dispose of undeployed air bag modules at normal refuse locations. Undeployed air bag modules contain substances that can cause severe illness or personal injury if sealed container is damaged during disposal.

Note. If vehicle is to be scrapped, perform on-vehicle air bag deployment procedure.

ON-VEHICLE DEPLOYMENT

  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Turn ignition switch OFF, remove key and put on safety glasses. Disconnect driver and passenger-side air bag module connectors. (Scheme 7)and (Scheme 8). Cut air bag module harness connector from vehicle leaving at least 6" of wire at connector.
  2. Strip 1/2" (13 mm) of insulation from each connector wire lead. Cut 2 15-foot deployment wires from 18-gauge multi-strand wire. Strip 1/2" (13 mm) of insulation from both ends of wires. Twist wires together at one end to short.
  3. Twist together one connector wire lead to other end of each deployment wire. (Scheme 9) Bend twisted connection flat and wrap tightly with electrical tape to insulate. Repeat this step for other connector wire lead.
  4. Remove all loose objects from front seat, and ensure no one is in vehicle. Connect deployment harness to air bag module connector. Stretch wires away from car as far as possible.
  5. Repeat steps 1) through 4) for passenger-side air bag module. Cover windshield and front door openings with a drop cloth.
  6. Separate wire ends. Connect each pair of wires to a 12-volt battery. Air bags should deploy. Disconnect wires from battery. DO NOT touch air bag module area for at least 10 minutes due to heat generated during deployment. Wear gloves and safety glasses before handling deployed air bag module. Wash hands with mild soap and water afterward. Deployed air bag modules can be disposed of like any other part. Repeat deployment procedure for passenger-side air bag.
  7. If air bag modules do not deploy, carefully remove from vehicle. See «AIR BAG MODULES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) under REMOVAL & INSTALLATION. Temporarily store module with trim facing up. Contact manufacturer for proper disposal instructions.

Scheme 9

Scheme 9
Scheme 9

OFF-VEHICLE DEPLOYMENT

  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Turn ignition switch OFF, remove key and put on safety glasses. Short 2 SIR Deployment Harness (J-38826) leads together by fully seating one banana plug into the other. Connect appropriate pigtail adapter to SIR deployment harness. (Scheme 10)
  2. Remove driver-side air bag module. See «AIR BAG MODULES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) under REMOVAL & INSTALLATION. Remove horn lead, redundant steering wheel control leads, horn buttons and steering wheel control buttons from air bag module, if applicable.
  3. Place air bag module with vinyl trim cover facing up, on a work bench or other surface (preferably paved surface outdoors) away from any loose or flammable objects. Clear space at least 6 feet in diameter around air bag. Extend SIR deployment harness and pigtail adapter to full length from air bag module. Place a 12-volt battery near shorted end of SIR deployment harness.
  4. Connect air bag module to pigtail adapter on SIR deployment harness. (Scheme 10) Ensure area around air bag module is clear of people or loose objects. Verify that air bag module is resting with trim cover facing up.
  5. Separate 2 banana plugs on SIR deployment harness. Connect SIR deployment harness wires to battery. (Scheme 10) Air bag module should deploy immediately. If air bag module does not deploy, go to next step. Disconnect SIR deployment harness from battery. Short 2 SIR deployment harness leads together. DO NOT touch metal surfaces of air bag module for at least 10 minutes due to heat generated during deployment. Wear gloves and safety glasses when handling deployed air bag module. Wash hands with mild soap and water after handling. Dispose of deployed air bag module as you would any other part. Inspect pigtail adapter and SIR deployment harness for damage after each use. Repeat deployment procedure for passenger-side air bag module.
  6. Ensure that SIR deployment harness is disconnected from battery and that 2 banana plugs have been shorted together. Disconnect pigtail adapter from air bag module. Temporarily store air bag module with trim cover facing up. Contact manufacturer for proper disposal instructions.

Scheme 10

Scheme 10
Scheme 10

POST-COLLISION INSPECTION

When a vehicle has been involved in a collision, certain components of the passive restraint system must be inspected or replaced. See PASSIVE RESTRAINT SYSTEM INSPECTION article in the GENERAL INFORMATION section for post-collision inspection information.

REMOVAL & INSTALLATION

WARNINGFailure to follow service precautions may result in air bag deployment and personal injury. See SERVICE PRECAUTIONS . After component replacement, check system operation. See SYSTEM OPERATION CHECK .

Removal

  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Disable air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system).
  2. Remove driver seat. Fold back carpet to access SDM. Remove Connector Position Assurance (CPA) clip and disconnect SDM harness connector. Remove SDM fasteners. (Scheme 11) Remove SDM.

Installation

To install, reverse removal procedure. Tighten bolts to 89 INCH lbs. (10 N.m). Activate air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM . Check system for proper operation. See SYSTEM OPERATION CHECK .

Scheme 11

Scheme 11: Installation
Scheme 11: Installation
  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Disable air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system).
  2. Front-end discriminating sensor is located below front-end lower tie bar. Remove CPA clip and disconnect sensor harness connector. Remove sensor mounting fasteners. Remove sensor. (Scheme 12)

To install, reverse removal procedure. Ensure arrow on sensor is installed pointing forward. Tighten fasteners to 89 INCH lbs. (10 N.m). Activate air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM . Check system for proper operation. See SYSTEM OPERATION CHECK .

Scheme 12

Scheme 12: Installation
Scheme 12: Installation
  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions) . Disable air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system) .
  2. Remove air bag module. See «AIR BAG MODULES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) . Remove horn contact from steering column. Remove steering wheel nut. Using Steering Wheel Puller and Legs (J-1859-A and J-36541), remove steering wheel.
  1. To install, reverse removal procedure. Align mark on steering wheel with mark on shaft, then install nut. Tighten nut to 30 ft. Lbs. (41 N.m). Install horn contact. Install driver-side air bag module. See «AIR BAG MODULES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) .
  2. Activate air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system) . Check system for proper operation. See «SYSTEM OPERATION CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__system-operation-check) .
  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Disable air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system).
  2. Remove driver-side air bag module. See «AIR BAG MODULES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). Remove steering wheel. See «STEERING WHEEL»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). Lower or remove steering column from vehicle.
  3. Remove lower steering column cover. Remove Torx screws from upper steering column cover. Remove steering column lock cylinder set and upper column cover. Remove coil assembly retaining ring. Remove coil assembly from shaft. (Scheme 13) Remove wave washer and wire harness straps.
  1. Ensure coil assembly hub and steering shaft are centered. Coil assembly will become uncentered if column is separated from steering gear and is allowed to rotate, or if centering spring is depressed, allowing hub to rotate while coil assembly is removed from column. To center coil assembly, see «CENTERING COIL ASSEMBLY»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__centering-coil-assembly) under ADJUSTMENTS.
  2. Ensure front wheels are in straight ahead position. Turn ignition to LOCK position. Install wave washer. To install coil assembly, align coil assembly with horn tower and slide onto shaft. Install retaining ring securely in groove on shaft. Route lower coil wire along steering column jacket assembly. (Scheme 13)
  3. Install wire straps to steering column wire harness. Position shift and multifunction lever seal to allow installation of column shrouds. Install upper column shroud and steering lock cylinder set. Install lower column shroud. Tighten upper column cover fasteners to 13 INCH lbs. (1.5 N.m) and lower column cover fasteners to 53 INCH lbs. (6 N.m). Install shift and multi-function lever seals. Raise or install steering column to vehicle.
  4. Install steering wheel. See «STEERING WHEEL»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). Install driver-side air bag module. See «AIR BAG MODULES»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). Activate air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system). Check system for proper operation. See «SYSTEM OPERATION CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__system-operation-check).

Scheme 13

Scheme 13
Scheme 13

Removal (Driver-Side)

  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Disable air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system).
  2. Turn steering wheel 90 degrees to gain access to rear steering wheel holes. Insert screw driver into each hole and push leaf springs to release air bag module retaining pins. Turn steering wheel 180 degrees to access remaining holes. Pull air bag module away from wheel. Disconnect air bag wire harness from clips on air bag module and steering wheel. Remove CPA clip and Yellow 2-pin connector from air bag module. Remove air bag module. (Scheme 14)
  1. Install CPA clip and air bag Yellow 2-pin connector to air bag module. Connect air bag wire harness to clips on steering wheel and air bag module. Install air bag module by pressing firmly into position on steering wheel to engage and latch leaf springs on notched pins. DO NOT pinch wires. (Scheme 14)
  2. Activate air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system). Check system for proper operation. See «SYSTEM OPERATION CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__system-operation-check).

Scheme 14

Scheme 14
Scheme 14

Removal (Passenger-Side)

  1. Before proceeding, see «SERVICE PRECAUTIONS»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__service-precautions). Disable air bag system. See «DISABLING & ACTIVATING AIR BAG SYSTEM»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__disabling-activating-air-bag-system).
  2. Remove passenger-side knee bolster. Remove CPA clip and disconnect connector from passenger-side air bag or trim cover. Remove fasteners. Remove passenger-side air bag module or trim cover. (Scheme 15)or (Scheme 16).

To install, reverse removal procedure. (Scheme 15)or (Scheme 16). Tighten fasteners to 89 INCH lbs. (10 N.m). Activate air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM. Check system for proper operation. See SYSTEM OPERATION CHECK.

Scheme 15

Scheme 15: Installation
Scheme 15: Installation

Scheme 16

Scheme 16
Scheme 16

SYSTEM OPERATION CHECK

If system is functioning normally, AIR BAG warning light flashes 7 times and then turns off when ignition switch is turned ON. System malfunction is indicated when light does not illuminate at all, light comes on while vehicle is driven, light flashes 7 times and remains on, or light does not flash but remains on when ignition switch is turned on.

SIR system faults are usually due to a disconnected or loose electrical connector caused by previous service on vehicle. Always check SIR coil connector at base of steering column for loose or damaged wiring.

DIAGNOSIS & TESTING

WARNINGFailure to follow service precautions may result in air bag deployment and personal injury. See SERVICE PRECAUTIONS . After component replacement, check system operation. See SYSTEM OPERATION CHECK .

DIAGNOSTIC TROUBLE CODES (DTCS)

Sensing & Diagnostic Module (SDM) provides a record of DTCs, stored according to type. SDM performs diagnostic monitoring of SIR system electrical components and sets a diagnostic trouble code (DTC) when a malfunction is detected. Current DTCs are stored in SDM and are erased when fault is corrected. Current DTCs can be read using a scan tool such as Tech 2.

SCAN TOOL DIAGNOSTICS

Scan Tool (Tech 2) reads and clears current and history codes. Ensure scan tool contains correct software cartridge for SIR diagnostics. To use scan tool, connect it to DLC connector, plug in power source and turn ignition switch to RUN position. Follow scan tool manufacturer instructions for communication with SIR system. Scan tool reads serial data from SDM data link output terminal No. 5 to DLC connector terminal No. 9.

DIAGNOSTIC PROCEDURES

Diagnostic procedures are designed to find and repair SIR malfunctions. It is important to use diagnostic charts and follow sequence listed below

Perform SIR System Diagnostic Check

SIR System Diagnostic Check should always be starting point for any SIR diagnostics. It checks for proper AIR BAG warning light operation and SIR trouble codes using both flash code and scan tool methods.

Refer to Proper Diagnostic Chart

SIR Diagnostic System Check indicates correct chart to diagnose SIR problems. Bypassing procedures may result in extended diagnostic time, incorrect diagnosis and incorrect parts replacement.

Repeat SIR Diagnostic System Check

Performing SIR Diagnostic System Check after all repair or diagnostic procedures ensures that repair has been made correctly and that no other conditions exist.

DIAGNOSTIC TESTS

Trouble CodePossible Cause
B1015Passenger Deployment Loop Resistance High
B1016Passenger Deployment Loop Resistance Low
B1017Passenger Deployment Loop Open
B1018Passenger Deployment Loop Short To Ground
B1019Passenger Deployment Loop Short To Voltage
B1021Driver Deployment Loop Resistance High
B1022Driver Deployment Loop Resistance Low
B1024Driver Deployment Loop Short To Ground
B1025Driver Deployment Loop Short To Voltage
B1026Driver Deployment Loop Open
B1035Discriminating Sensor Closed Or Short To Ground
B1036Discriminating Sensor Open Or Short To Voltage
B1051Deployment Commanded
B1053Deployment Commanded With Loop Malfunction
B1061SIR Warning Light Malfunction
B1071Internal SDM Malfunction

DIAGNOSTIC TROUBLE CODE (DTC) CHART

SIR DIAGNOSTIC SYSTEM CHECK

WARNINGTo avoid air bag deployment and injury when trouble shooting system, only use test equipment specified in diagnostic charts. Carefully follow all instructions.

Circuit Description

Ignition switch supplies IGNITION POSITIVE VOLTAGE to SDM at terminal No. 10 using AIR BAGS fuse. When ignition switch is turned to RUN, SDM responds by flashing AIR BAG warning light 7 times, then turning off while performing tests on SIR system.

Diagnostic Procedure

  1. Observe AIR BAG warning light while turning ignition switch to RUN position. If AIR BAG warning light flashes 7 times, go to step 3 . If AIR BAG warning light does not flash 7 times, go to next step.
  2. If AIR BAG warning light comes on steady, see «AIR BAG WARNING LIGHT COMES ON STEADY»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) . If AIR BAG warning light does not come on, see «AIR BAG WARNING LIGHT DOES NOT COME ON»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) .
  3. Observe AIR BAG warning light after it flashes 7 times. If AIR BAG warning light turns off, go to step 7 . If AIR BAG warning light does not turn off, go to next step.
  4. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to read Diagnostic Trouble Code (DTC). If a current DTC is displayed, go to step 6 . If no current DTC is displayed, go to next step.
  5. If scan tool indicates no data received, check malfunction in data link communications system. If scan tool does not indicate no data received, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) .
  6. Turn ignition off. Read DTCs. If DTCs B1018, B1024 or B1051 are displayed, refer to Diagnostic Procedure for specific DTC. Diagnose remaining current DTCs from lowest to highest. If only history DTCs exist, refer to Diagnostic Aids for specific DTC. A history DTC indicates malfunction has been repaired or is intermittent.
  7. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to read Diagnostic Trouble Code (DTC). If a history DTC is displayed, go to step 9 . If no history DTC is displayed, go to next step.
  8. If scan tool indicates no data received, check malfunction in data link communications system. If scan tool does not indicate no data received, system is okay at this time.
  9. Turn ignition off. Read DTCs. If DTC B1071 is set, see «DTC B1071: INTERNAL SDM FAILURE»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__dtc-b1071-internal-sdm-failure) . For all other DTCs, refer to Diagnostic Aids for specific DTC. A history DTC indicates malfunction has been repaired or is intermittent.

When SDM recognizes IGNITION POSITIVE VOLTAGE applied to terminal No. 10 is greater than 8.2 volts, AIR BAG warning light is flashed 7 times to verify operation. At this time SDM performs POWER-ON tests followed by RESISTANCE MEASUREMENT test and CONTINUOUS MONITORING tests. When a malfunction is detected, SDM sets a current DTC and turns AIR BAG warning light ON. SDM clears current DTCs and moves them to a history file when malfunction is no longer detected or ignition switch is cycled, except for DTCs B1018, B1024, B1051, B1053 and B1071. DTCs B1018, B1024, B1051, and B1053 will not clear using scan tool CLEAR CODES. Repair malfunction that set DTC before replacing SDM.

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .
  2. Turn ignition off. Reconnect all SIR components and ensure all components are properly mounted. Wait 30 seconds after ignition is turned off. Turn ignition on and observe air bag warning light. If light flashes 7 times and goes off, symptom or DTC is no longer occurring. Clear SIR DTCs and repeat «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) . If light does not flash 7 times and go off, go to next step. NOTE: It is extremely unlikely that a malfunctioning SDM would cause a new malfunction to occur during diagnostic process.
  3. Using scan tool, read DTC display. If same symptom or DTC occurs as when SIR Diagnostic System Check was first performed, go to next step. If not, refer to diagnostic procedure for appropriate malfunction.
  4. Clear SIR DTCs. Turn ignition off and wait 30 seconds. Turn ignition on and observe air bag warning light. If light flashes 7 times and goes off, symptom or DTC is no longer occurring. Clear SIR DTCs and repeat «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) . If light does not flash 7 times and go off, go to next step.
  5. Turn ignition off. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation) .
  6. Reconnect all SIR components and ensure all components properly mounted. Repeat «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .

Ignition switch applies battery voltage to AIR BAG warning light, connected to AIR BAG WARNING INDICATOR terminal No. 7 using GAUGES fuse. AIR BAGS fuse applies battery voltage to IGNITION POSITIVE VOLTAGE input, terminal No. 10. SDM responds by flashing AIR BAG warning light 7 times. If IGNITION POSITIVE VOLTAGE is outside normal operating range (8.2-17.1 volts), AIR BAG warning light will come ON steady with no DTCs set.

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. If scan tool IGNITION voltage is greater than 8.2 volts, go to next step. If scan tool IGNITION voltage is less or equal to 8.2 volts, go to step 14.
  3. Set parking brake and start engine. Follow scan tool instructions to request SIR data list display. If scan tool IGNITION voltage is greater than 17.1 volts, check charging system. If scan tool IGNITION voltage is less or equal to 17.1 volts, go to next step.
  4. Turn ignition off. Inspect Sensing and Diagnostic Module (SDM) harness connector CPA clip. (Scheme 11) If CPA clip is properly installed, go to step 6. If CPA clip is not properly installed, go to next step.
  5. Install CPA clip securely and go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  6. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Disconnect SDM harness connector. (Scheme 11) Install SIR Shorting Bar (J-38715-96) to SDM harness connector. Install CPA. Turn ignition on. If AIR BAG warning light comes on steady, go to next step. If AIR BAG warning light does not come on, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  7. Turn ignition off. Remove SIR shorting bar from SDM harness connector. Inspect SDM harness connector internal shorting bar. If shorting bar is damaged or corroded, go to next step. If shorting bar is not damaged or corroded, go to step 9.
  8. Replace SDM harness connector. Go to step 28.
  9. Install SIR shorting bar to SDM harness connector. Install CPA. Disconnect instrument cluster connector. Measure resistance between SDM harness connector terminal No. 7 and ground. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to step 13.
  10. Disconnect circuit 1751 from ground circuit G202. Measure resistance between SDM harness connector terminals No. 6 and 7. (Scheme 1) If resistance is less than infinite, go to step 12. If resistance is infinite, go to next step.
  11. Repair short to ground in circuit 358. Go to step 28.
  12. Repair short between circuits 358 and 1751. Inspect circuit 1751 for any cut or chafed wires. Go to step 28.
  13. Replace instrument cluster. Go to step 28.
  14. Turn ignition off. Remove and inspect AIR BAGS fuse. If fuse is okay, go to step 20. If fuse is blown, go to next step.
  15. Replace AIR BAGS fuse. Turn ignition on for 10 seconds, then turn off. Remove and inspect AIR BAGS fuse. If fuse is okay, go to step 19. If fuse is blown, go to next step.
  16. Disconnect SDM. (Scheme 11) Replace AIR BAGS fuse. Turn ignition on for 10 seconds, then turn off. Remove and inspect AIR BAGS fuse. If fuse is okay, go to step 25. If fuse is blown, go to next step.
  17. Repair short to ground in circuit 1139. Connect SDM. Replace AIR BAGS fuse. Go to step 28.
  18. Replace SDM. See SENSING & DIAGNOSTIC MODULE under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 28.
  19. Install AIR BAGS fuse. Go to step 28.
  20. Inspect SDM harness connector. If connector is secure, go to step 22. If connector is not secure, go to next step.
  21. Properly connect SDM harness connector and install CPA. Go to step 28.
  22. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Disconnect SDM. (Scheme 11) Check for proper connection to SDM at terminal No. 10. (Scheme 1) If SDM harness connector terminal No. 10 is damaged or corroded, go to next step. If SDM harness connector terminal No. 10 is not damaged or corroded, go to step 24.
  23. Replace SDM harness connector. Go to step 28.
  24. Inspect SDM terminals. If terminals are damaged or corroded, go to next step. If terminals are not damaged or corroded, go to step 26.
  25. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 28.
  26. Measure resistance between SDM harness connector terminal No. 10 and fuse No. 1 holder terminal. (Scheme 1) If resistance is 0-5 ohms, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If resistance is greater than 5 ohms, go to next step.
  27. Repair open in circuit 1139. Go to next step.
  28. Reconnect all SIR system components. Ensure that all components are properly mounted. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

Description

When ignition switch is turned to RUN, GAGES fuse applies battery voltage to AIR BAG warning light, connected to SDM at AIR BAG WARNING INDICATOR terminal No. 7. AIR BAGS fuse applies battery voltage to SDM IGNITION POSITIVE VOLTAGE input, terminal No. 10. SDM responds by flashing AIR BAG warning light 7 times.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Set parking brake. Turn ignition on. If brake indicator comes on, go to next step. If brake indicator does not come on, go to step 13.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Disconnect SDM. (Scheme 11) Install SIR Shorting Bar (J-38715-96) to SDM harness connector. Install CPA. Turn ignition on. Measure voltage between SDM harness connector terminal No. 7 and ground. (Scheme 1) If voltage is greater than 10 volts, go to next step. If voltage is 10 volts or less, go to step 6.
  4. Turn ignition off. Disconnect instrument cluster connector. Turn ignition on. Measure voltage between SDM harness connector terminal No. 7 and ground. (Scheme 1) If voltage is less than one volt, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If voltage is one volt or greater, go to next step.
  5. Turn ignition off. Repair short to voltage in circuit 358. Reconnect instrument cluster connector. Go to step 22.
  6. Turn ignition off. Remove instrument cluster. Check for proper connection to instrument cluster connector terminal A11. If connector terminal is damaged or corroded, go to next step. If connector terminal is not damaged or corroded, go to step 8.
  7. Repair instrument cluster harness connector. Go to step 24.
  8. Remove and inspect AIR BAG warning light bulb. If bulb is okay, go to step 10. If bulb is bad, go to next step.
  9. Replace AIR BAG warning light bulb. Install instrument cluster. Go to step 24.
  10. Measure resistance between instrument cluster harness connector terminal A16 and SDM harness connector terminal No. 7. (Scheme 1) If resistance is 0-5 ohms, go to step 12. If resistance is greater than 5 ohms, go to next step.
  11. Repair open in circuit 358. Install instrument cluster. Go to step 24.
  12. Replace instrument cluster. Go to step 24.
  13. Turn ignition off. Remove and inspect GAUGES fuse. If fuse is okay, go to step 19 ). If fuse is blown, go to next step.
  14. Replace fuse. Turn ignition on for 10 seconds, then turn off. Remove and inspect GAUGES fuse. If fuse is okay, go to step 18. If fuse is blown, go to next step.
  15. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Disconnect instrument cluster. Replace GAUGES fuse. Turn ignition on for 10 seconds and then turn ignition off. Reinspect GAUGES fuse. If fuse is okay, go to step 17. If fuse is blown, go to next step.
  16. Repair short to ground in circuit 39. Replace GAUGES fuse. Go to step 24.
  17. Replace instrument cluster. Install GAUGES fuse. Go to step 24.
  18. Install GAUGES fuse. Go to step 24.
  19. Remove instrument cluster. Inspect connection to instrument cluster connector terminal B17. If connector terminal is damaged or corroded, go to next step. If connector terminal is okay, go to step 21.
  20. Repair instrument cluster harness connector. Go to step 24.
  21. Measure resistance between instrument cluster connector terminal B17 and GAUGES fuse holder terminal. If resistance is 0-5 ohms, go to step 23. If resistance is greater than 5 ohms, go to next step.
  22. Repair open in circuit 39. Install GAUGES fuse. Go to step 24.
  23. Repair open in power feed circuit. Install GAUGES fuse. Go to next step.
  24. Reconnect all SIR system components. Ensure that all components are properly mounted. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE and deployment voltages are measured to ensure they are within normal ranges. SDM then performs RESISTANCE MEASUREMENT test. PASSENGER LOW terminal No. 4 is grounded through an internal current sink, and PASSENGER HIGH terminal No. 1 is connected to an internal constant current source. By monitoring voltage difference between PASSENGER HIGH and PASSENGER LOW, SDM calculates combined resistance of passenger deployment loop using measured voltage.

Conditions For Setting DTC

DTC sets when driver and passenger deployment loops are not open or shorted to voltage, passenger deployment loop is not shorted to ground, and passenger deployment loop resistance is greater than 3 ohms. RESISTANCE MEASUREMENT test occurs only once each ignition cycle when IGNITION POSITIVE VOLTAGE is in normal range.

Action Taken

SDM turns on AIR BAG warning light and sets DTC.

Conditions For Clearing DTC

Current DTC clears when ignition switch is cycled and resistance is less than 3 ohms. History DTC clears when scan tool CLEAR CODES is received or when 250 malfunction-free ignition cycles have occurred. If CLEAR CODES is received, and DTC still exists, DTC will not reappear until next ignition cycle.

Diagnostic Aids

An intermittent condition is likely to be caused by a poor connection at passenger-side air bag connector terminals "A" or "B", SDM terminals No. 1 or 4, or a poor wire to terminal connection in circuits 1403 or 1404.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger deployment loop resistance PASSENGER RESISTANCE. Go to next step.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Check for proper connection at terminals "A" and "B" on passenger-side air bag Yellow 2-pin harness connector. (Scheme 4)or (Scheme 5). If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 6.
  4. Replace passenger-side air bag Yellow 2-pin harness connector. Go to next step.
  5. Check for proper connection at terminals "A" and "B" on passenger-side air bag Yellow 2-pin harness connector. (Scheme 4)or (Scheme 5). If terminals are damaged or corroded, go to step 7. If terminals are okay, go to step 21.
  6. Check for proper connection at terminals "A" and "B" on passenger-side air bag Yellow 2-pin harness connector. (Scheme 4)or (Scheme 5). If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 8.
  7. Replace passenger-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 21.
  8. Reconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger deployment loop resistance. If resistance is greater than 3 ohms, go to step 10. If resistance is 3 ohms or less, go to next step.
  9. Turn ignition off. Replace passenger-side air bag connector. Go to step 21.
  10. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read passenger deployment loop resistance. If resistance is greater than 3 ohms, go to step 12. If resistance is 3 ohms or less, go to next step.
  11. Turn ignition off. Replace passenger-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 21.
  12. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Inspect for proper connection at SDM harness connector terminals No. 1 and 4. (Scheme 1) If harness connector is damaged or corroded, go to next step. If harness connector is okay, go to step 15.
  13. Replace SDM harness connector. Go to next step.
  14. Inspect for proper connection at SDM harness connector terminals No. 1 and 4. (Scheme 1) If terminals are damaged or corroded, go to step 16. If terminals are okay, go to step 21).
  15. Inspect for proper connection at SDM terminals No. 1 and 4. If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 17.
  16. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 21 ).
  17. Zero Digital Multimeter (J-39200). Measure resistance between SDM harness connector terminal No. 1 and passenger-side air bag Yellow 2-pin harness connector terminal "A". (Scheme 1), (Scheme 4) and (Scheme 5). If resistance is 0-0.5 ohms, go to step 19. If resistance is greater than 0.5 ohms, go to next step.
  18. Repair high resistance condition in circuit 1403. Go to step 21.
  19. Measure resistance between SDM harness connector terminal No. 4 and passenger-side air bag Yellow 2-pin harness connector terminal "B". (Scheme 1), (Scheme 4) and (Scheme 5). If resistance is 0-0.5 ohms, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If resistance is greater than 0.5 ohms, go to next step.
  20. Repair high resistance condition in circuit 1404. Go to next step.
  21. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  22. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE and deployment voltages are measured to ensure they are within normal ranges. SDM then performs RESISTANCE MEASUREMENT test. PASSENGER LOW terminal No. 4 is grounded through an internal current sink, and PASSENGER HIGH terminal No. 1 is connected to an internal constant current source. By monitoring voltage difference between PASSENGER HIGH and PASSENGER LOW, SDM calculates combined resistance of passenger deployment loop using measured voltage.

DTC sets when driver and passenger deployment loops are not open or shorted to voltage, passenger deployment loop is not shorted to ground, and passenger deployment loop resistance is less than 1.4 ohms. Test occurs only once each ignition cycle when IGNITION POSITIVE VOLTAGE is in normal range.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when ignition switch is cycled and resistance is greater than 1.4 ohms. History DTC clears when scan tool CLEAR CODES is received or when 250 malfunction-free ignition cycles have occurred. If CLEAR CODES is received, and DTC still exists, DTC will not reappear until next ignition cycle.

An intermittent condition is likely to be caused by a short between circuit 1403 and circuits 347, 348, or 1404, or a malfunctioning shorting bar on passenger-side air bag connector.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger deployment loop resistance. If DTC B1022 is also indicated, go to next step. If DTC B1022 is not indicated, go to step 4.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Repair short between circuits 347 and 1403. Go to step 12.
  4. Turn ignition off. Disconnect passenger-side air bag Yellow 2-pin connector located behind passenger-side knee bolster. (Scheme 8) Reconnect harness connector and ensure CPA is installed correctly. Turn ignition on. Using scan tool, request SIR data list display. Read passenger deployment loop resistance. If resistance is less than 1.4 ohms, go to step 6. If resistance is 1.4 ohms or greater, go to next step.
  5. Turn ignition off. Replace passenger-side air bag harness connector. Go to step 12.
  6. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read passenger deployment loop resistance. If resistance is less than 1.4 ohms, go to step 8. If resistance is 1.4 ohms or greater, go to next step.
  7. Turn ignition off. Replace passenger-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 12.
  8. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Measure resistance between SDM harness connector terminals No. 1 and 4. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to step 10.
  9. Turn ignition off. Repair short between circuits 1403 and 1404. Go to step 12.
  10. Measure resistance between SDM harness connector terminals No. 1 and 3. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  11. Repair short between circuits 1403 and 348. Go to next step.
  12. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  13. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. SDM measures to ensure IGNITION POSITIVE VOLTAGE is within normal range. SDM then performs DEPLOYMENT LOOP CONTINUITY test, measuring voltage difference between PASSENGER HIGH and PASSENGER LOW.

DTC sets when voltage difference between PASSENGER HIGH terminal No. 1 and PASSENGER LOW terminal No. 4 is greater than or equal to 400 millivolts for 500 milliseconds during DEPLOYMENT LOOP CONTINUITY, RESISTANCE MEASUREMENT, or CONTINUOUS MONITORING tests.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when voltage difference between PASSENGER HIGH terminal No. 1 and PASSENGER LOW terminal No. 4 is less than 400 millivolts for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

An intermittent condition is likely to be caused by a poor connection at passenger-side air bag connector terminals "A" or "B", SDM terminals No. 1 or 4, or an open in circuits 1403 or 1404.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger deployment loop voltage difference PASSENGER VDIF. Go to next step.
  3. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind glove box door. (Scheme 7)and (Scheme 8). Check for proper connection at terminals "A" and "B" on harness side of passenger-side air bag Yellow 2-pin connector. (Scheme 4)or (Scheme 5). If terminals are damage or corroded, go to next step. If okay, go to step 6.
  4. Replace passenger-side air bag harness Yellow 2-pin connector. Go to next step.
  5. Check for proper connection at passenger-side air bag harness Yellow 2-pin connector terminals "A" and "B". (Scheme 4)or (Scheme 5). If terminals are damaged or corroded, go to step 7. If terminals are okay, go to step 21.
  6. Check for proper connection at passenger-side air bag harness Yellow 2-pin connector terminals "A" and "B". (Scheme 4)or (Scheme 5). If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 8.
  7. Replace passenger-side air bag jumper harness. Go to step 21.
  8. Connect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger deployment loop voltage difference PASSENGER VDIF. If PASSENGER VDIF is less than 400 millivolts, go to next step. If PASSENGER VDIF is 400 millivolts or greater, go to step 10.
  9. Turn ignition off. Replace passenger-side air bag harness Yellow 2-pin connector. Go to step 21.
  10. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read and record passenger deployment loop voltage difference PASSENGER VDIF. If PASSENGER VDIF is less than 400 millivolts, go to next step. If PASSENGER VDIF is 400 millivolts or greater, go to step 12.
  11. Turn ignition off. Replace passenger-side air bag harness Yellow 2-pin connector. Go to step 21.
  12. Turn ignition off. Disconnect load tool from harness connectors. Disconnect SDM. (Scheme 11) Inspect for proper connection at SDM harness connector terminals No. 1 and 4. (Scheme 1) If terminals are damaged or corroded, go to next step. If terminals are not damaged or corroded, go to step 15.
  13. Replace SDM harness connector. Go to next step.
  14. Inspect for proper connection at SDM harness connector terminals No. 1 and 4. (Scheme 1) If terminals are damaged or corroded, go to step 16. If terminals are not damaged or corroded, go to step 21.
  15. Inspect for proper connection at SDM harness connector terminals No. 1 and 4. (Scheme 1) If terminals are damaged or corroded, go to next step. If terminals are not damaged or corroded, go to step 17.
  16. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 21.
  17. Zero Digital Multimeter (J-39200). Measure resistance between SDM harness connector terminal No. 1 and passenger-side air bag Yellow 2-pin harness connector terminal "A". (Scheme 1), (Scheme 4) and (Scheme 5). If resistance is 0-0.5 ohms, go to step 19. If resistance is greater than 0.5 ohms, go to next step.
  18. Repair open or high resistance condition in circuit 1403. Go to step 21.
  19. Measure resistance between SDM harness connector terminal No. 4 and passenger-side air bag Yellow 2-pin harness connector terminal "B". (Scheme 1), (Scheme 4) and (Scheme 5). If resistance is 0-0.5 ohms, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If resistance is greater than 0.5 ohms, go to next step.
  20. Repair open or high resistance condition in circuit 1404. Go to next step.
  21. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  22. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE, 23 VLR and deployment loop voltages are measured to ensure they are within normal ranges. SDM monitors voltages at DRIVER LOW terminal No. 3 and PASSENGER LOW terminal No. 4 to detect shorts to ground in air bag module circuits. Service wait time is 10 minutes. See DISABLING & ACTIVATING AIR BAG SYSTEM before replacing SIR components.

DTC sets when driver and passenger deployment loops are not open, driver deployment loop is not shorted to voltage, voltage at DRIVER LOW is greater than 3.3 volts, voltage at PASSENGER LOW is less than 3.3 volts for 500 milliseconds during POWER-ON, RESISTANCE MEASUREMENT, or CONTINUOUS MONITORING tests, and IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM turns on AIR BAG warning light and sets DTCs B1018 and B1071.

DTC clears when malfunction no longer occurs (has been repaired) and SDM has been replaced. DTC B1018 is a latched code and cannot be cleared.

An intermittent condition is likely to be caused by a short to ground in passenger-side air bag module circuit. DTC B1018 would be accompanied by DTC B1071. Inspect circuits 1403 and 1404 carefully for cutting or chafing. If wiring pigtail of passenger-side air bag module is damaged, component must be replaced. Careful inspection of circuits and components indicated on DTC B1018 chart is essential to ensure that replacement SDM is not damaged.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger low voltage PASSENGER SENSELO. If voltage is less than 3.3 volts, go to next step. If voltage is 3.3 volts or greater, go to DIAGNOSTIC AIDS.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read passenger low voltage PASSENGER SENSELO. If voltage is less than 3.3 volts, go to step 5. If voltage is 3.3 volts or greater, go to next step.
  4. Turn ignition off. Inspect passenger-side air bag pigtail for damage and proper routing. Replace passenger-side air bag module. Go to step 9.
  5. Turn ignition off. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Measure resistance between SDM harness connector terminals No. 1 and 6. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to step 7.
  6. Repair short to ground in circuit 1403. Go to step 9.
  7. Measure resistance between SDM harness connector terminals No. 4 and 6. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  8. Repair short to ground in circuit 1404. Go to next step.
  9. Reconnect all SIR components. Ensure that all components are properly mounted. Turn ignition on. Ensure PASSENGER SENSELO is greater than 3.3 volts. Replace SDM. See «SENSING & DIAGNOSTIC MODULE (SDM)»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) under REMOVAL & INSTALLATION. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE, 23 VLR and deployment loop voltages are measured to ensure they are within normal ranges. SDM monitors voltages at DRIVER LOW terminal No. 3 and PASSENGER LOW terminal No. 4 to detect shorts to voltage in air bag module circuits.

DTC sets when voltage at DRIVER LOW terminal No. 3 is less than 4.8 volts, voltage at PASSENGER LOW terminal No. 4 is greater than 4.8 volts for 500 milliseconds during CONTINUOUS MONITORING test, and IGNITION POSITIVE VOLTAGE is within normal operation range.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when voltage at PASSENGER LOW terminal No. 4 is less than 4.8 volts for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

An intermittent condition is likely to be caused by a short to voltage in passenger-side air bag module circuit. Inspect circuits 1403 and 1404 carefully for cutting or chafing. If wiring pigtail of passenger-side air bag module is damaged, component must be replaced.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record passenger low voltage PASSENGER SENSELO. Go to next step.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read passenger low voltage PASSENGER SENSELO. If voltage is greater than 4.8 volts, go to step 5. If voltage is 4.8 volts or less, go to next step.
  4. Turn ignition off. Replace passenger-side air bag module. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 9.
  5. Turn ignition off. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Turn ignition on. Measure voltage between SDM harness connector terminals No. 1 and 6. (Scheme 1) If voltage is less than one volt, go to step 7. If voltage is one volt or greater, go to next step.
  6. Turn ignition off. Repair short to voltage in circuit 1403. Go to step 9.
  7. Measure voltage between SDM harness connector terminals No. 4 and 6. (Scheme 1) If voltage is less than one volt, go to next step. If voltage is one volt or greater, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  8. Turn ignition off. Repair short to voltage in circuit 1404. Go to next step.
  9. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  10. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE and deployment loop voltages are measured to ensure they are within normal ranges. SDM then performs RESISTANCE MEASUREMENT test. DRIVER LOW terminal No. 3 is grounded through a current sink and a constant current source is connected to DRIVER HIGH terminal No. 2. By monitoring voltage difference between DRIVER HIGH and DRIVER LOW, SDM calculates resistance of driver deployment loop using measured voltage.

DTC sets when driver and passenger deployment loops are not open or shorted to voltage, driver deployment loop is not shorted to ground, and driver deployment loop resistance is greater than 3.8 ohms during RESISTANCE MEASUREMENT test. Test is run once each ignition cycle when IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when driver deployment loop resistance is less than 3.8 ohms and ignition switch is cycled. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred. When scan tool CLEAR CODES is received and fault still exists, DTC will not reappear until next ignition cycle.

An intermittent condition is likely to be caused by poor connection at terminals "A" or "B" of SIR coil connector, terminals "A" or "B" of driver-side air bag connector, SDM terminals No. 2 and 3, or a poor wire to terminal connection in circuit 347 or 348. Note and compare value of driver deployment loop resistance over multiple ignition cycles to determine intermittent condition.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver deployment loop resistance DRIVER RESISTANCE. Go to next step.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Check for proper connection at terminals "A" and "B" on driver-side air bag Yellow 2-pin harness connector. (Scheme 3) If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 6.
  4. Replace driver-side air bag Yellow 2-pin harness connector. Go to next step.
  5. Check for proper connection at terminals "A" and "B" on SIR coil side of connector. (Scheme 3) If terminals are damaged or corroded, go to step 7. If terminals are okay, go to step 23.
  6. Check for proper connection at terminals "A" and "B" on SIR coil side of connector. (Scheme 3) If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 8.
  7. Replace SIR coil. See SIR COIL ASSEMBLY under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  8. Reconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver deployment loop resistance DRIVER RESISTANCE. If resistance is greater than 3.8 ohms, go to step 10. If resistance is 3.8 ohms or less, go to next step.
  9. Turn ignition off. Replace driver-side Yellow 2-pin harness connector at base of steering column. Go to step 23.
  10. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read driver deployment loop resistance DRIVER RESISTANCE. If resistance is greater than 3.8 ohms, go to step 14. If resistance is 3.8 ohms or less, go to next step.
  11. Turn ignition off. Remove driver-side air bag module. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Install SIR Driver/Passenger Load Tool (J-38715-A) to upper SIR connector on steering column. Turn ignition on. Using scan tool, request SIR data list display. Read driver deployment loop resistance DRIVER RESISTANCE. If resistance is greater than 3.8 ohms, go to step 13. If resistance is 3.8 ohms or less, go to next step.
  12. Turn ignition off. Replace driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  13. Replace SIR coil. See SIR COIL ASSEMBLY under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  14. Turn ignition off. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Inspect for proper connection at SDM harness connector terminals No. 2 and 3. (Scheme 1) If harness connector is damaged or corroded, go to next step. If harness connector is okay, go to step 17.
  15. Replace SDM harness connector. Go to next step.
  16. Inspect for proper connection at SDM terminals No. 2 and 3. (Scheme 1) If terminals are damaged or corroded, go to step 18. If terminals are okay, go to step 23.
  17. Inspect for proper connection at SDM harness connector terminals No. 2 and 3. (Scheme 1) If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 19.
  18. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  19. Measure resistance between SDM harness connector terminal No. 2 and driver-side air bag Yellow 2-pin harness connector terminal "A". (Scheme 1)and (Scheme 3). If resistance is 0-0.5 ohms, go to step 21). If resistance is greater than 0.5 ohms, go to next step.
  20. Repair high resistance condition in circuit 347. Go to step 23.
  21. Measure resistance between SDM harness connector terminal No. 3 and driver-side air bag Yellow 2-pin harness connector terminal "B". If resistance is 0-0.5 ohms, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If resistance is greater than 0.5 ohms, go next step.
  22. Repair high resistance condition in circuit 348. Go next step.
  23. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  24. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE and deployment loop voltages are measured to ensure they are within normal ranges. SDM then performs RESISTANCE MEASUREMENT test. DRIVER LOW terminal No. 3 is grounded through a current sink and an internal constant current source is connected to DRIVER HIGH terminal No. 2. By monitoring voltage difference between DRIVER HIGH and DRIVER LOW, SDM calculates resistance of driver deployment loop using measured voltage.

DTC sets when driver and passenger deployment loops are not open or shorted to voltage, driver deployment loop is not shorted to ground, and resistance is less than 1.7 ohms during RESISTANCE MEASUREMENT test. Test is run once each ignition cycle when IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when driver deployment loop resistance is greater than 1.7 ohms and ignition switch is cycled. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred. When scan tool CLEAR CODES is received and fault still exists, DTC will not reappear until next ignition cycle.

An intermittent condition is likely to be caused by a short between circuit 347 and circuits 348, 1403, or 1404, or a malfunctioning shorting bar on driver-side air bag connector or SIR coil connector. Note and compare value of driver deployment loop resistance over multiple ignition cycles to determine intermittent condition.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver deployment loop resistance. If DTC B1016 is also indicated, go to next step. If DTC B1016 is not indicated, go to step 4.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Repair short between circuits 347 and 1403. Go to step 14.
  4. Turn ignition off. Disconnect driver-side air bag Yellow 2-pin connector located at base of steering column. (Scheme 7) Reconnect 2-pin connector. Inspect CPA for proper installation. Turn ignition on. Using scan tool, request SIR data list display. Read driver deployment loop resistance. If resistance is less than 1.7 ohms, go to step 6. If resistance is 1.7 ohms or greater, go to next step.
  5. Turn ignition off. Replace driver-side air bag Yellow 2-pin connector at base of steering column. Go to step 14.
  6. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read driver deployment loop resistance. If resistance is less than 1.7 ohms, go to step 10. If resistance is 1.7 ohms or greater, go to next step.
  7. Turn ignition off. Remove driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Install SIR Driver/Passenger Load Tool (J-38715-A) to upper SIR connector on steering column. Turn ignition on. Using scan tool, request SIR data list display. Read driver deployment loop resistance DRIVER RESISTANCE. If resistance is less than 1.7 ohms, go to step 9. If resistance is 1.7 ohms or greater, go to next step.
  8. Turn ignition off. Replace driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 14.
  9. Turn ignition off. Replace SIR coil. See SIR COIL under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 14.
  10. Turn ignition off. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Measure resistance between SDM harness connector terminals No. 2 and 3. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to step 12.
  11. Repair short between circuits 347 and 348. Go to step 14.
  12. Measure resistance between SDM harness connector terminals No. 2 and 4. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  13. Repair short between circuits 347 and 1404. Go to next step.
  14. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  15. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE, 23 VLR and deployment loop voltages are measured to ensure they are within normal ranges. SDM monitors voltages at DRIVER LOW terminal No. 3 and PASSENGER LOW terminal No. 4 to detect shorts to ground in air bag module circuits. Service wait time is 10 minutes. See DISABLING & ACTIVATING AIR BAG SYSTEM before replacing SIR components.

DTC sets when driver and passenger deployment loops are not open, passenger deployment loop is not shorted to voltage, voltage at PASSENGER LOW terminal NO. 4 is greater than 3.3 volts, and voltage at DRIVER LOW terminal No. 3 is less than 3.3 volts for 500 milliseconds during POWER-ON, RESISTANCE MEASUREMENT, or CONTINUOUS MONITORING tests, and IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM turns on AIR BAG warning light and sets DTC.

DTC clears when malfunction no longer occurs (has been repaired) and SDM has been replaced. DTC B1024 is a latched code and cannot be cleared.

An intermittent condition is likely to be caused by a short to ground in driver-side air bag module circuit. Inspect circuits 347 and 348 carefully for cutting or chafing. Careful inspection of circuits and components indicated on DTC B1024 chart is essential to ensure that replacement SDM is not damaged. DTC B1024 will be accompanied by DTC B1071. Note and compare value of driver deployment loop resistance over multiple ignition cycles to determine intermittent condition.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver low voltage DRIVER SENSELO. Go to next step.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read driver low voltage DRIVER SENSELO. If voltage is less than 3.3 volts, go to step 7. If voltage is 3.3 volts or greater, go to next step.
  4. Turn ignition off. Remove driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Disconnect SIR Driver/Passenger Load Tool (J-38715-A) from driver-side 2-pin harness connector. Connect driver-side 2-pin harness connector at base of steering column. (Scheme 7) Connect SIR driver/passenger load tool to SIR coil connector on steering column. Turn ignition on. Using scan tool, request SIR data list display. Read driver low voltage DRIVER SENSELO.If voltage is less than 3.3 volts, go to step 6. If voltage is 3.3 volts or greater, go to next step.
  5. Replace driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 11.
  6. Turn ignition off. Replace SIR coil. See SIR COIL ASSEMBLY under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 11.
  7. Turn ignition off. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Measure resistance between SDM harness connector terminals No. 2 and 6. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to step 9.
  8. Repair short to ground in circuit 347. Go to step 11.
  9. Measure resistance between SDM harness connector terminal No. 3 and known-good ground. (Scheme 1) If resistance is less than infinite, go to next step. If resistance is infinite, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  10. Repair short to ground in circuit 348. Go to next step.
  11. Reconnect all SIR components. Ensure that all components are properly mounted. Turn ignition on. Ensure DRIVER SENSELO is greater than 3.3 volts. Replace SDM. See «SENSING & DIAGNOSTIC MODULE (SDM)»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) under REMOVAL & INSTALLATION. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE, 23 VLR and deployment loop voltages are measured to ensure they are within normal ranges. SDM monitors voltages at DRIVER LOW terminal No. 3 and PASSENGER LOW terminal No. 4 to detect shorts to voltage in air bag module circuits.

DTC sets when voltage at PASSENGER LOW terminal No. 4 is less than 4.8 volts, voltage at DRIVER LOW terminal No. 3 is greater than 4.8 volts for 500 milliseconds during CONTINUOUS MONITORING test, and IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when voltage at DRIVER LOW terminal No. 3 is less than 4.8 volts for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

An intermittent condition is likely to be caused by a short to voltage in air bag module circuit. Inspect circuits 347 and 348 carefully for cutting or chafing. Note and compare value of DRIVER SENSELO to determine intermittent condition.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver low voltage DRIVER SENSELO. Go to next step.
  3. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read driver low voltage DRIVER SENSELO. If voltage is greater than 4.8 volts, go to step 7. If voltage is 4.8 volts or less, go to next step.
  4. Turn ignition off. Remove driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Disconnect SIR Driver/Passenger Load Tool (J-38715-A) from driver-side 2-pin harness connector. Connect driver-side 2-pin harness connector at base of steering column. (Scheme 7) Connect SIR driver/passenger load tool to SIR coil connector on steering column. Turn ignition on. Using scan tool, request SIR data list display. Read driver low voltage DRIVER SENSELO.If voltage is greater than 4.8 volts, go to step 6. If voltage is 4.8 volts or less, go to next step.
  5. Replace driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 11.
  6. Turn ignition off. Remove SIR coil. See SIR COIL ASSEMBLY under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Inspect coil and wires for damage. Replace SIR coil. Go to step 11.
  7. Turn ignition off. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Turn ignition on. Measure voltage between SDM harness connector terminals No. 2 and 6. If voltage is less than one volt, go to step 9. If voltage is one volt or greater, go to next step.
  8. Turn ignition off. Repair short to voltage in circuit 347. Go to step 11.
  9. Measure voltage between SDM harness connector terminals No. 3 and known-good ground. (Scheme 1) If voltage is less than one volt, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If voltage is one volt or greater, go to next step.
  10. Turn ignition off. Repair short to voltage in circuit 348. Go to next step.
  11. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  12. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. SDM measures to ensure IGNITION POSITIVE VOLTAGE is within normal range. During DEPLOYMENT LOOP CONTINUITY test, SDM measures voltage difference between DRIVER HIGH and DRIVER LOW.

DTC sets when voltage difference between DRIVER HIGH terminal No. 2 and DRIVER LOW terminal No. 3 is greater than or equal to 400 millivolts for 500 milliseconds during DEPLOYMENT LOOP CONTINUITY, RESISTANCE MEASUREMENT, or CONTINUOUS MONITORING tests.

SDM turns on AIR BAG warning light and sets DTC.

Current DTC clears when voltage difference between DRIVER HIGH terminal No. 2 and DRIVER LOW terminal No. 3 is less than 400 millivolts for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

An intermittent condition is likely to be caused by a poor connection at driver-side air bag module terminals "A" or "B", SIR coil assembly terminals "A" or "B", SDM terminals No. 2 or 3, or an open in circuit 347 or 348. An intermittent open in SIR coil assembly could also set this DTC. To test for bad SIR coil assembly, clear DTCs, then turn steering wheel back and forth with ignition switch in RUN position. If AIR BAG warning light comes ON and DTC B1026 has set again, SIR coil assembly is probably malfunctioning.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver deployment loop voltage difference DRIVER VDIF. Go to next step.
  3. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Check for proper connection at terminals "A" and "B" on harness side of driver-side air bag Yellow 2-pin connector. (Scheme 3) If terminals are damage or corroded, go to next step. If okay, go to step 6.
  4. Replace driver-side air bag harness Yellow 2-pin connector. Go to next step.
  5. Check for proper connection at driver-side air bag harness Yellow 2-pin connector terminals "A" and "B". (Scheme 3) If terminals are damaged or corroded, go to step 7. If terminals are okay, go to step 23.
  6. Check for proper connection at driver-side air bag harness Yellow 2-pin connector terminals "A" and "B". (Scheme 3) If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 8.
  7. Replace SIR coil. See SIR COIL ASSEMBLY under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  8. Connect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Turn ignition on. Follow scan tool instructions to request SIR data list display. Read and record driver deployment loop voltage difference DRIVER VDIF. If DRIVER VDIF is less than 400 millivolts, go to next step. If DRIVER VDIF is 400 millivolts or greater, go to step 10.
  9. Turn ignition off. Replace driver-side air bag harness Yellow 2-pin connector. Go to step 23.
  10. Turn ignition off. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Install SIR Driver/Passenger Load Tool (J-38715-A) to harness connectors. Turn ignition on. Using scan tool, request SIR data list display. Read and record driver deployment loop voltage difference DRIVER VDIF. If DRIVER VDIF is less than 400 millivolts, go to next step. If DRIVER VDIF is 400 millivolts or greater, go to step 14.
  11. Turn ignition off. Remove driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Disconnect SIR Driver/Passenger Load Tool (J-38715-A) from driver-side 2-pin harness connector. Connect driver-side 2-pin harness connector at base of steering column. (Scheme 7) Connect SIR driver/passenger load tool to SIR coil connector on steering column. Turn ignition on. Using scan tool, request SIR data list display. Read and record driver deployment loop voltage difference DRIVER VDIF. If DRIVER VDIF is less than 400 millivolts, go to next step. If DRIVER VDIF is 400 millivolts or greater, go to step 13.
  12. Turn ignition off. Replace driver-side air bag. See AIR BAG MODULES under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  13. Turn ignition off. Replace SIR coil. See SIR COIL ASSEMBLY under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  14. Disconnect SDM. (Scheme 11) Disconnect SIR driver/passenger load tool from harness connectors. Inspect for proper connection at SDM harness connector terminals No. 2 and 3. (Scheme 1) If terminals are damaged or corroded, go to next step. If terminals are not damaged or corroded, go to step 17.
  15. Replace SDM harness connector. Go to next step.
  16. Inspect for proper connection at SDM terminals No. 2 and 3. (Scheme 1) If terminals are damaged or corroded, go to step 18. If terminals are not damaged or corroded, go to step 23.
  17. Inspect for proper connection at SDM terminals No. 2 and 3. (Scheme 1) If terminals are damaged or corroded, go to next step. If terminals are not damaged or corroded, go to step 19.
  18. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 23.
  19. Zero Digital Multimeter (J-39200). Measure resistance between SDM harness connector terminal No. 2 and driver-side air bag Yellow 2-pin harness connector terminal "A". (Scheme 1)and (Scheme 3). If resistance is 0-0.5 ohms, go to step 21. If resistance is greater than 0.5 ohms, go to next step.
  20. Repair open in circuit 347. Go to step 23.
  21. Measure resistance between SDM harness connector terminal No. 3 and driver-side air bag Yellow 2-pin harness connector terminal "B". (Scheme 1)and (Scheme 3). If resistance is 0-0.5 ohms, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If resistance is greater than 0.5 ohms, go to next step.
  22. Repair open in circuit 348. Go to next step.
  23. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  24. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE, 23 VLR and deployment loop voltages are measured to ensure they are within normal ranges. SDM then performs CONTINUOUS MONITORING. SDM contains a resistor network connected to 5 volts, ground, and SDM front-end sensor signal terminal No. 9. One K/ohm resistor in front-end discriminating sensor, parallel to normally open switch, provides a parallel path to ground. This causes a specified percentage of voltage to appear at SDM front-end sensor signal input. This voltage is monitored to detect shorts to ground or a closed discriminating sensor.

DTC sets when SDM is configured for front-end discriminating sensor, voltage at SENSOR FEED terminal No. 9 is less than 0.5 volts for 500 milliseconds during CONTINUOUS MONITORING test, and IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM sets DTC and commands IPC to turn on AIR BAG warning light.

Current DTC clears when voltage at SENSOR FEED terminal No. 9 is greater than 2.4 volts for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

An intermittent condition is likely to be caused by a short to ground in discriminating sensor circuit. Inspect circuit 349 carefully for cutting or chafing.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Disconnect front-end discriminating sensor. (Scheme 12) Measure resistance between sensor terminals "A" and "B". (Scheme 2) If resistance is greater than 950 ohms, go to step 4. If resistance is 950 ohms or less, go to next step.
  3. Replace front-end discriminating sensor. See FRONT-END DISCRIMINATING SENSOR under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 8.
  4. Disconnect SDM harness connector. (Scheme 11) Measure resistance between front-end discriminating sensor harness connector terminal "A" and ground. (Scheme 2) If resistance is less than infinite, go to next step. If resistance is infinite, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system).
  5. Disconnect C114 connector. Measure resistance between connector C114 terminal "A" and ground. If resistance is less than infinite, go to next step. If resistance is infinite, go to step 7.
  6. Repair short to ground in circuit 349 between connector C114 and sensor connector. Go to step 8.
  7. Repair short to ground in circuit 349 between connector C114 and SDM connector. Go to next step.
  8. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  9. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

When ignition switch is turned to RUN position, SDM performs tests to diagnose critical internal malfunctions. IGNITION POSITIVE VOLTAGE, 23 VLR and deployment loop voltages are measured to ensure they are within normal ranges. SDM then performs CONTINUOUS MONITORING. SDM contains a resistor network connected to 5 volts, ground, and to SDM sensor signal terminal No. 9. One K/ohm resistor in front-end discriminating sensor, parallel to normally open switch, provides a parallel path to ground. This causes a specified percentage of voltage to appear at SDM sensor signal input. This voltage is monitored to detect shorts to voltage or an open discriminating sensor.

DTC sets when SDM is configured for front-end discriminating sensor, voltage at SENSOR FEED terminal No. 9 is greater than 5 volts for 500 milliseconds during CONTINUOUS MONITORING test, and IGNITION POSITIVE VOLTAGE is within normal operating range.

SDM sets DTC and commands IPC to turn on AIR BAG warning light.

Current DTC clears when voltage at SENSOR FEED is less than 3.2 volts for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

An intermittent condition is likely to be caused by a broken or chafed wire in discriminating sensor circuit. Inspect circuits 349 and 1751 carefully for cutting or chafing.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).
  2. Turn ignition off. Disconnect front-end discriminating sensor. (Scheme 12) Check for proper connection at sensor harness connector terminals "A" and "B". (Scheme 2) If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 5.
  3. Replace sensor harness connector. Go to next step.
  4. Check for proper connection at sensor harness connector terminals "A" and "B". (Scheme 2) If terminals are damaged or corroded, go to step 6. If terminals are okay, go to step 19.
  5. Check for proper connection at sensor harness connector terminals "A" and "B". (Scheme 2) If terminals are damaged or corroded, go to next step. If terminals are okay, go to step 7.
  6. Replace front-end discriminating sensor. See FRONT-END DISCRIMINATING SENSOR under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 27.
  7. Measure resistance between sensor terminals "A" and "B". (Scheme 2) If resistance is greater than 1050 ohms, go to step 6. If resistance is 1050 ohms or less, go to next step.
  8. Measure resistance between sensor harness connector terminal "B" and ground. (Scheme 2) If resistance is 0-5 ohms, go to step 14. If resistance is greater than 5 ohms, go to next step.
  9. Disconnect C114 connector. Inspect connector C114 terminal "B" for damage or corrosion. If terminal is damaged or corroded, go to next step. If terminal is okay, go to step 11.
  10. Replace connector C114. Go to step 27.
  11. Measure resistance between discriminating sensor harness connector terminal "B" and connector C114 terminal "B". (Scheme 2) If resistance is 0-5 ohms, go to next step. If resistance is greater than 5 ohms, go to step 13.
  12. Repair open in circuit 1751 between connector C114 and ground G202. Go to step 27.
  13. Repair open in circuit 1751 between connector C114 and discriminating sensor connector. Go to step 27.
  14. Disconnect SDM. (Scheme 11) Inspect SDM connector terminal No. 9. (Scheme 1) If terminal is damaged or corroded, go to next step. If terminal is okay, go to step 17.
  15. Replace SDM connector. Go to next step.
  16. Inspect SDM terminal No. 9. If terminal is damaged or corroded, go to step 18. If terminal is okay, go to step 27.
  17. Inspect SDM terminal No. 9. If terminal is damaged or corroded, go to step 18. If terminal is okay, go to step 19.
  18. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation). Go to step 27.
  19. Disconnect driver and passenger-side air bag Yellow 2-pin connectors located at base of steering column and behind passenger-side knee bolster. (Scheme 7)and (Scheme 8). Measure resistance between front-end discriminating sensor harness connector terminal "A" and SDM harness connector terminal No. 9. (Scheme 1)and (Scheme 2). If resistance is 0-5 ohms, go to step 25. If resistance is greater than 5 ohms, go to next step.
  20. Disconnect C114 connector. Inspect connector C114 terminal "A". If terminal is damaged or corroded, go to next step. If terminal is okay, go to step 22.
  21. Replace connector C114. Go to step 27.
  22. Measure resistance between discriminating sensor connector terminal "A" and connector C114 terminal "A". (Scheme 2) If resistance is 0-5 ohms, go to next step. If resistance is greater than 5 ohms, go to step 24.
  23. Repair open in circuit 349 between connector C114 and SDM connector. Go to step 27.
  24. Repair open in circuit 349 between connector C114 and discriminating sensor connector. Go to step 27.
  25. Turn ignition on. Measure voltage between sensor harness connector terminal "A" and ground. (Scheme 2) If voltage is less than one volt, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system). If voltage is one volt or greater, go to next step.
  26. Turn ignition off. Repair short to voltage in circuit 349. Go to next step.
  27. Reconnect all SIR components. Ensure that all components are properly mounted. Go to next step.
  28. Clear all SIR DTCs. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check).

SDM contains a sensing device which converts vehicle velocity changes to an electrical signal. Electrical signal is processed by SDM and compared to a value stored in memory. When signal exceeds stored value, additional signal processing is performed and signals are compared to values stored in memory. When 2 signals exceed stored values, SDM causes current to flow through air bag modules, deploying air bags and causing DTC B1051 to set.

DTC sets when SDM detects a frontal crash, up to 30 degrees off centerline of vehicle, of sufficient force to warrant deployment of air bags.

SDM sets DTC, turns on AIR BAG warning light, and records crash data.

DTC clears when malfunction no longer occurs (has been repaired) and SDM has been replaced. DTC B1051 is a latched code and cannot be cleared.

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .
  2. Turn ignition off. If air bags have deployed, go to step 5 . If air bags have not deployed, go to next step.
  3. Inspect front of vehicle and undercarriage for signs of impact. If impact has occurred, go to step 5 . If no impact has occurred, go to next step.
  4. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation) . Go to step 6 .
  5. Replace components and perform inspections as required following an accident. See «POST-COLLISION INSPECTION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__post-collision-inspection) .
  6. Reconnect all SIR components. Ensure that all components are properly mounted. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .

SDM contains a sensing device which converts vehicle velocity changes to an electrical signal. Electrical signal is processed by SDM and compared to a value stored in memory. When signal exceeds stored value, additional signal processing is performed and signals are compared to values stored in memory. When 2 signals exceed stored values, SDM will cause current to flow through air bag modules, deploying air bags. DTC B1053 will set when a deployment occurs while an inflator circuit fault exists that could result in a non-deployment situation in one or both air bag modules.

DTC sets when SDM detects a frontal crash, up to 30 degrees off centerline of vehicle, of sufficient force to warrant deployment of air bags.

SDM sets DTC, turns on AIR BAG warning light, and records crash data.

DTC clears when malfunction no longer occurs (has been repaired) and SDM has been replaced. DTC B1053 is a latched code and cannot be cleared.

DTC B1053 will be accompanied by another DTC (other than DTC B1071). Repair malfunction causing other DTCs before installing new SDM.

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .
  2. Turn ignition off. If air bags have deployed, go to step 5 . If air bags have not deployed, go to next step.
  3. Inspect front of vehicle and undercarriage for signs of impact. If impact has occurred, go to step 5 . If no impact has occurred, go to next step.
  4. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM) under «REMOVAL & INSTALLATION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__removal-installation) . Go to step 6 .
  5. Replace components and perform inspections as required following an accident. See «POST-COLLISION INSPECTION»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__post-collision-inspection) .
  6. Reconnect all SIR components. Ensure that all components are properly mounted. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .

With ignition key in OFF/UNLOCK position, AIR BAG indicator will illuminate steady. When ignition switch is first turned to RUN position, AIR BAGS fuse applies system voltage to IGNITION POSITIVE VOLTAGE input at terminal No. 10. SDM responds by commanding instrument cluster, via serial data (CKT 800), to flash AIR BAG indicator 7 times. If serial data communication is lost between SDM and instrument cluster, AIR BAG indicator will come on steady with a DTC B1061 set. If IGNITION POSITIVE VOLTAGE to SDM is outside normal operating range, AIR BAG indicator will come on steady with no DTCs set.

DTC sets when SDM receives AIR BAG indicator fault message 5 consecutive times, via serial data from instrument cluster and SDM has not received a request from instrument cluster to communicate, via serial data, for 6 seconds.

SDM sets DTC and attempts to turn on AIR BAG warning light.

Current DTC clears when ignition switch is cycled. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

Refer to AIR BAG WARNING LIGHT COMES ON STEADY and AIR BAG WARNING LIGHT DOES NOT COME ON to diagnose warning light circuit malfunctions.

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .
  2. Turn ignition on. Clear SIR DTCs. Using scan tool, request SIR DTC display. If DTC B1061 is indicated, go to «SDM INTEGRITY CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) . If DTC B1061 is not indicated, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .

DTC B1071: INTERNAL SDM FAILURE

Note. When DTC B1018 or B1024 has been set, DTC B1071 sets, and SDM must be replaced. When scan tool CLEAR CODES is received and malfunction no longer exists, DTCs B1018 or B1024 and B1071 will remain current. Ensure short to ground condition is repaired prior to installing replacement SDM to avoid damage to component.

DTC B1071 indicates potential internal SDM malfunction.

DTC sets when any of the following conditions are detected by SDM

1) 23 VLR voltage is out of normal operating range during POWER-ON or CONTINUOUS MONITORING tests.

2) Crash data recording reserve voltage discharge time failure for 3 consecutive ignition cycles during POWER-ON test.

3) Calculated checksum for internal memory does not match stored value during POWER-ON test.

4) Driver or passenger deployment loop is shorted to ground during CONTINUOUS MONITORING tests.

5) Accelerometer is malfunctioning during POWER-ON or CONTINUOUS MONITORING tests.

6) Driver or passenger current source is malfunctioning during RESISTANCE MEASUREMENT test.

7) Temporary memory storage area is malfunctioning during POWER-ON test.

8) SDM is unable to read from or write to EEPROM during POWER-ON test.

9) Arming sensor inside SDM is not closed during deployment event.

10) Voltage measured at DRIVER LOW and PASSENGER LOW is too low during POWER-ON or CONTINUOUS MONITORING tests.

11) Device in SDM that arms system for deployment is malfunctioning during POWER-ON or CONTINUOUS MONITORING tests.

12) Permanent memory storage area is malfunctioning during POWER-ON test.

SDM sets DTC and turns on AIR BAG warning light.

Current DTC clears when malfunction has not been detected for 500 milliseconds. History DTC clears when scan tool CLEAR CODES is received or 250 malfunction-free ignition cycles have occurred.

Note. For circuit number and wire color identification, see WIRING DIAGRAMS .

  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .
  2. If DTC B1018 is indicated, go to «DTC B1018: PASSENGER DEPLOYMENT LOOP SHORT TO GROUND»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) . If DTC B1018 is not indicated, go to next step.
  3. If DTC B1024 is indicated, go to «DTC B1024: DRIVER DEPLOYMENT LOOP SHORT TO GROUND»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) . If DTC B1024 is not indicated, go to next step.
  4. Replace SDM. See «SENSING & DIAGNOSTIC MODULE (SDM)»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system) under REMOVAL & INSTALLATION. Go to «SIR DIAGNOSTIC SYSTEM CHECK»(/gmc/savana/i-1996-2002/remont/airbag/#supplemental-inflatable-restraint-system__sir-diagnostic-system-check) .

WIRE REPAIR

SIR system requires special wiring repair procedures due to sensitive nature of circuitry. Wire Repair Kit (J-38125-B) contains special sealed splices for use in repairing SIR wiring. Splices use a heat shrink sleeve with sealing adhesive to produce a sealed splice and a cross-hatched core crimp to produce a positive contact for low energy circuits.

Repair damaged SIR wire harness connectors and terminals (except pigtails) using connector repair assembly packs and splice crimping tool provided. Terminals in SIR system are manufactured from a special metal to provide necessary contact integrity for sensitive, low-energy circuits. These terminals are only available in connector repair assembly packs, and no other terminal should be substituted.

If individual terminals on SDM harness connector are damaged, SDM harness connector must be replaced using SDM harness connector pigtail assembly or SDM harness connector replacement kit. If individual terminals on any other SIR connector are damaged, entire connector must be replaced. Use appropriate connector repair assembly pack. Replace entire SIR wire harness, if necessary to maintain SIR circuit integrity.

DO NOT make wiring, connector or terminal repairs on components with wiring pigtails. If a wiring pigtail is damaged, entire component (including pigtail) should be replaced.

Any wiring other than a pigtail can be repaired by splicing in a new section of wire of same gauge. Sealed splices and crimping tool must be used for these splices. Open wire harness by removing tape as necessary, using a sewing seam ripper. Refer to instructions in kit for wiring repair procedure.

TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
Steering Wheel Nut30 (41)
INCH Lbs. (N.m)
Front-End Discriminating Sensor Fasteners89 (10)
Knee Bolster Bolt
Driver-Side89 (10)
Passenger-Side35 (4)
Passenger-Side Air Bag Module Fasteners89 (10)
Passenger-Side Trim Cover Fasteners89 (10)
Sensing & Diagnostic Module (SDM) Bolt89 (10)
Steering Column Upper Cover Fasteners13 (1.5)
Steering Column Lower Cover Fasteners53 (6)

TORQUE SPECIFICATIONS

SIR System Wiring Diagrams (All Models). Scheme 17

Scheme 17: SIR System Wiring Diagrams (All Models)
Scheme 17: SIR System Wiring Diagrams (All Models)