Part 1 of 5
SIX-STEP TROUBLESHOOTING PROCEDUREDiagnosis of the body system is done in six basic steps:
- verification of complaint
- verification of any related symptoms
- symptom analysis
- problem isolation
- repair of isolated problem
- verification of proper operation
SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION
The body system on the 2001 RS consists of a combination of modules that communicate over the PCI bus (Programmable Communication Interface multiplex system). Through the PCI bus, information about the operation of vehicle components and circuits is relayed quickly to the appropriate module(s). All modules receive all the information transmitted on the bus even though a module may not require all information to perform its function. It will only respond to messages "addressed" to it through binary coding process. This method of data transmission significantly reduces the complexity of the wiring in the vehicle and the size of wiring harnesses. All of the information about the functioning of all the systems is organized, controlled, and communicated by the PCI bus, which is described in the Communication of this general information.
AIRBAG SYSTEM/OCCUPANT RESTRAINT CONTROLLER SYSTEM
The 2001 Minivan Airbag System contain the following components: Occupant Restraint Controller (ORC), Airbag Warning Indicator, Clockspring, Driver and Passenger Airbags, Seat belt Tensioners (SBT), Hall-effect Seat Belt Switches (SBS), Left and Right Side Airbag Control Module (SIACM), and Seat (mounted side) Airbags.
The Occupant Restraint Controller (ORC) is a new type of Airbag Control Module (ACM) that supports staged airbag deployment. Staged deployment is the ability to trigger airbag system squib inflators all at once or individually as needed to provide the appropriate restraint for the severity of the impact. The ORC has four major functions: PCI Bus communications, onboard diagnostics, impact sensing, and component deployment. The ORC also contains an energy-storage capacitor. This capacitor stores enough electrical energy to deploy the front airbag components for two seconds following a battery disconnect or failure during an impact. The ORC is secured to the floor panel transmission tunnel below the instrument panel inside the vehicle. The ORC cannot be repaired or adjusted and must be replaced.
The ORC sends and/or receives PCI Bus messages with the Instrument Cluster (MIC), Body Control Module (BCM), and Powertrain Control Module (PCM). Diagnostic trouble codes will be set if the communication with these modules is lost or contains invalid information.
The microprocessor in the ORC monitors the impact sensor signal and the airbag system electrical circuits to determine the system readiness. The ORC also monitors bus messages from both SIACM. If the ORC detects a monitored system fault or SIACM fault, it sends a message to the instrument cluster via PCI bus to turn on the airbag warning indicator. The ORC can set both active and stored diagnostic trouble codes to aid in the diagnosing system problems. See ORC/SIACM DIAGNOSTIC TROUBLE CODES.
The ORC has an internal accelerometer that senses the rate of vehicle deceleration, which provides verification of the direction and severity of an impact. A pre-programmed decision algorithm in the ORC microprocessor determines when the deceleration rate is severe enough to require airbag system protection. The Occupant Restraint Controller (ORC) also uses the driver and front passenger seat belt switch status (buckled or unbuckled) as inputs to determine the level of airbag deployment, low, medium, or high as well as whether or not the seat belt tensioners should deploy. The ORC also uses the crash severity to determine the level of driver and front passenger deployment, low medium or high. When the programmed conditions are met, the ORC sends an electrical signal to deploy the appropriate airbag system components.
WARNING: THE AIRBAG SYSTEM IS A SENSITIVE, COMPLEX ELECTRO-MECHANICAL UNIT. BEFORE ATTEMPTING TO DIAGNOSE OR SERVICE ANY AIRBAG SYSTEM OR RELATED STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENTS YOU MUST FIRST DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE. WAIT TWO MINUTES FOR THE SYSTEM CAPACITOR TO DISCHARGE BEFORE FURTHER SYSTEM SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO DO THIS COULD RESULT IS ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY. NEVER STRIKE OR KICK THE AIRBAG CONTROL MODULE, AS IT CAN DAMAGE THE IMPACT SENSOR OR AFFECT ITS CALIBRATION. IF AN AIRBAG CONTROL MODULE IS ACCIDENTALLY DROPPED DURING SERVICE, THE MODULE MUST BE SCRAPPED AND REPLACED WITH A NEW UNIT.
The airbag warning lamp is the only point at which the customer can observe symptoms of a system malfunction. Whenever the ignition key is turned to the run or start position, the MIC performs a lamp check by turning the airbag warning indicator on for 6 - 8 seconds. After the lamp check, if the indicator turns ON, it means that the ORC has checked the system and found it to be free of discernible malfunctions. If the lamp remains ON, there could be an active fault in the system or the MIC lamp circuit may be internally shorted to ground. If the lamp comes ON and stays ON for a period longer than 6 - 8 seconds then goes OFF, there is usually an intermittent problem in the system.
Driver Airbag
The airbag protective trim cover is the most visible part of the driver side airbag system. The protective trim cover is fitted to the front of the airbag module and forms a decorative cover in the center of the steering wheel. The module is mounted directly to the steering wheel. Located under the trim cover are the horn switch, the airbag cushion, and the airbag cushion supporting components. The airbag module includes a housing to which the cushion and hybrid inflator are attached and sealed. The 2001 Minivan is equipped with driver airbag with dual stage inflators that include a small canister of highly compressed argon gas. The Occupant Restraint Controller (ORC) uses vehicle crash severity, driver seat belt switch status (buckled or unbuckled) as inputs to determine the level of airbag deployment. When supplied with the proper electrical signal, the hybrid inflator or inflators discharge the compressed gas it contains directly into the cushion. The airbag module cannot be repaired, and must be replaced if deployed or in any way damaged.
WARNING: THE DRIVER AIRBAG MODULE CONTAINS ARGON GAS PRESSURIZED TO OVER 17236.89 Kpa (2500 PSI). DO NOT ATTEMPT TO DISMANTLE AN AIRBAG MODULE OR TAMPER WITH ITS INFLATOR. DO NOT PUNCTURE, INCINERATE, OR BRING INTO CONTACT WITH ELECTRICITY. DO NOT STORE AT TEMPERATURE EXCEEDING 93 °C (200 °F). REPLACE AIRBAG SYSTEM COMPONENTS ONLY BUT INTERNAL DIFFERENCES MAY RESULT IN INFERIOR OCCUPANT PROTECTION. THE FASTENERS, SCREWS, AND BOLTS ORIGINALLY USED FOR THE AIRBAG SYSTEM COMPONENTS HAVE SPECIAL COATINGS AND ARE SPECIFICALLY DESIGNED FOR THE AIRBAG SYSTEM. THEY MUST NEVER BE REPLACED WITH ANY SUBSTITUTES. ANY TIME A NEW FASTENER IS NEEDED, REPLACE IT WITH THE CORRECT FASTENERS PROVIDED IN THE SERVICE PACKAGE OR SPECIFIED IN THE MOPAR PARTS CATALOG.
CAUTION: DEPLOYED FRONT AIR BAGS MAY OR MAY NOT HAVE LIVE PYROTECHNIC MATERIAL WITHIN THE AIR BAG INFLATOR. DO NOT DISPOSE OF 2001 MODEL YEAR DRIVER AND PASSENGER AIRBAGS UNLESS YOU ARE SURE OF COMPLETE DEPLOYMENT. PLEASE REFER TO THE HAZARDOUS SUBSTANCE CONTROL SYSTEM FOR PROPER DISPOSAL. DISPOSE OF DEPLOYED AIR BAGS IN A MANNER CONSISTENT WITH STATE, PROVINCIAL, LOCAL, AND FEDERAL REGULATIONS. USE THE FOLLOWING TABLE TO IDENTIFY THE STATUS OF THE AIRBAG SQUIB.
Airbag Squib Status
1. Using a DRBIII(R) read Airbag DTC's If the following active codes are present:
If neither of the following codes is an active code:
ACTIVE DTC SQUIB STATUS
Driver squib 1 open Status of Airbag is
Driver Squib 2 open Unknown.
Clockspring
The clockspring is mounted on the steering column behind the steering wheel. This assembly consist of a plastic housing which contains a flat, ribbon-like, electrically conductive tape that winds and unwinds with the steering wheel rotation. The clockspring is used to maintain a continuous electrical circuit between the instrument panel wiring and the driver airbag, the horn, and the vehicle speed control switches if equipped. The clockspring must be properly centered when it is reinstalled on the steering column following any service procedure, or it could be damaged. The clockspring cannot be repaired and it must be replaced.
Passenger Airbag
The airbag door in the instrument panel top cover the glove box is the most visible part of the passenger side airbag system. The airbag door has a living hinge at the top, which is secured to the instrument panel top cover. Located under the airbag door is the airbag cushion and its supporting components. The airbag module includes a housing to which the cushion and hybrid inflators are attached and sealed. The 2001 Minivan is equipped with front passenger airbag with dual stage inflators that include a small canister of highly compressed argon gas. The ORC uses vehicle crash severity, front passenger seat belt switch status (buckled or unbuckled) inputs to determine the level of airbag deployment. When supplied with the proper electrical signal, the hybrid inflator or inflators discharge the compressed gas it contains directly into the cushion. The airbag module cannot be repaired, and must be replaced if deployed or in any way damaged.
WARNING: THE PASSENGER AIRBAG MODULE CONTAINS ARGON GAS PRESSURIZED TO 17236.89 Kpa (2500 PSI). DO NOT ATTEMPT TO DISMANTLE AN AIRBAG MODULE OR TAMPER WITH ITS INFLATOR. DO NOT PUNCTURE, INCINERATE, OR BRING INTO CONTACT WITH ELECTRICITY. DO NOT STORE AT TEMPERATURE EXCEEDING 93 °C (200 °F). REPLACE AIRBAG SYSTEM COMPONENTS ONLY WITH PARTS SPECIFIED IN THE MOPAR PARTS CATALOG. SUBSTITUTE PARTS MAY APPEAR INTERCHANGEABLE, BUT INTERNAL DIFFERENCES MAY RESULT IN INFERIOR OCCUPANT PROTECTION. THE FASTENERS, SCREWS, AND BOLTS ORIGINALLY USED FOR THE AIRBAG SYSTEM COMPONENTS HAVE SPECIAL COATINGS AND ARE SPECIFICALLY DESIGNED FOR THE AIRBAG SYSTEM. THEY MUST NEVER BE REPLACED WITH ANY SUBSTITUTES. ANY TIME A NEW FASTENER IS NEEDED, REPLACE IT WITH THE CORRECT FASTENERS PROVIDED IN THE SERVICE PACKAGE OR SPECIFIED IN THE MOPAR PARTS CATALOG.
CAUTION: DEPLOYED FRONT AIR BAGS MAY OR MAY NOT HAVE LIVE PYROTECHNIC MATERIAL WITHIN THE AIR BAG INFLATOR. DO NOT DISPOSE OF 2001 MOPAR YEAR DRIVER AND PASSENGER AIRBAGS UNLESS YOU ARE SURE OF COMPLETE DEPLOYMENT. PLEASE REFER TO THE HAZARDOUS SUBSTANCE CONTROL SYSTEM FOR PROPER DISPOSAL. DISPOSE OF DEPLOYED AIR BAGS IN A MANNER CONSISTENT WITH STATE, PROVINCIAL, LOCAL, AND FEDERAL REGULATIONS. USE THE FOLLOWING TABLE TO IDENTIFY THE STATUS OF THE AIRBAG SQUIB.
Airbag Squib Status
1. Using a DRBIII(R) read Airbag DTC's If the following active codes are present:
If neither of the following codes is an active code:
ACTIVE DTC SQUIB STATUS
Passenger squib 1 open Status of Airbag is
Passenger squib 2 open Unknown.
Seat Belt Tensioner (SBT)
The driver and passenger seat belt (buckle) tensioners are mounted to the inboard side of the front seats. The seat belt buckle and seat belt switch are connected directly to the seat belt tensioner cable. At the onset of an impact event the ORC uses the seat belt tensioner to rapidly retract the seat belt buckles. With the slack removed, the occupant's forward motion in an impact will be reduced as will the likelihood of contacting interior components. The seat belt tensioner cannot be removed, the occupant's forward motion in an impact will be reduced as will the likelihood of contacting repaired, if damaged or defective it must be replaced. The ORC continuously monitors the resistance of the seat belt tensioner circuits an open or shorted conditions.
Seat Belt Switches (SBS)
The hall-effect driver and front passenger seat belt switches provide the seat belt status, buckled or unbuckled, via hardwired inputs to the ORC. The ORC uses seat belt switch inputs to determine the appropriate level of airbag deployment. If the seat belt switches are damaged or defective the seat belt tensioner must be replaced. The ORC continuously monitors the seat belt switch circuits for an open or shorted conditions.
Side Impact Airbag Control Module (SIACM)
Supplemental driver and front passenger seat airbags provide side impact protection for the front seat occupants. Each side airbag has it own side impact airbag control module (SIACM) to provide independent impact sensing and deployment. SIACM are located on the left and right B post just above the seat belt retractor. One, same part number, side impact airbag control module (SIACM) is used on both side of the vehicle. However, for proper PCI bus operation each SIACM must have a unique module identification. To provide the unique module identification for both, left and right, the SIACM software looks for a ground on cavity # 5 of the SIACM connector. If cavity # 5 is grounded the SIACM communicates as a left SIACM otherwise it communicates as a right SIACM. The SIACM performs self diagnostics and circuit tests to determine if the system is functioning properly. If the test finds a problem the SIACM will set both active and stored diagnostic trouble codes. If a DTC is active the SIACM will request that the airbag warning lamp be turned ON. The results of the system test are transmitted on the PCI Bus to the ORC once each second or on change in lamp state. If the warning lamp status message from the either SIACM contains a lamp ON request, the ORC will set an active DTC. At the same time as the DTC is set the ORC sends a PCI Bus message to the mechanical instrument cluster (MIC) requesting the airbag warning lamp be turned ON. Observe all ORC warning and caution statements when servicing or handling the SIACM. SIACM are not repairable and must be replaced if they are dropped.
WARNING: THE AIRBAG SYSTEM IS A SENSITIVE, COMPLEX ELECTROMECHANICAL UNIT. BEFORE ATTEMPTING TO DIAGNOSE OR SERVICE ANY AIRBAG SYSTEM OR RELATED STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENTS YOU MUST FIRST DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE. WAIT TWO MINUTES FOR THE SYSTEM CAPACITOR TO DISCHARGE BEFORE FURTHER SYSTEM SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO DO THIS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY. NEVER STRIKE OR KICK THE AIRBAG CONTROL MODULE, AS IT CAN DAMAGE THE IMPACT SENSOR OR AFFECT ITS CALIBRATION. IF AN AIRBAG CONTROL MODULE IS ACCIDENTALLY DROPPED DURING SERVICE, THE MODULE MUST BE SCRAPPED AND REPLACED WITH A NEW UNIT.
The airbag warning lamp is the only point at which the customer can observe symptoms of a system malfunction. Whenever the ignition key is turned to the run or start position, the MIC performs a lamp check by turning the airbag warning indicator on for 6 - 8 seconds. After the lamp check, if the indicator turns ON, it means that the ORC has checked the system and found it to be free of discernible malfunctions. If the lamp remains ON, there could be an active fault in the system or the MIC lamp circuit may be internally shorted to ground. If the lamp comes ON and stays on for a period longer than 6 - 8 seconds then goes OFF, there is usually an intermittent problem in the system.
Seat Airbags (SAB)
The left and right seat airbag modules are located in the outboard end of the front seat backs. The airbag module contains a bag, an inflator (a small canister of highly compressed argon gas) and a mounting bracket. The seat airbag module cannot be repaired and must be replaced if deployed or in any way damaged. When supplied with the proper electrical signal the inflator seals the hole in the airbag cushion so it can discharge the compressed gas it contains directly into the cushion. Upon deployment, the seat back trim cover will tear open and allow the seat airbag to fully deploy between the seat and the door.
WARNING: SEAT AIRBAG CONTAINS ARGON GAS PRESSURIZED TO OVER 17236.89 Kpa (2500 PSI). DO NOT ATTEMPT TO DISMANTLE AN AIRBAG MODULE OR TAMPER WITH ITS INFLATOR. DO NOT PUNCTURE, INCINERATE, OR BRING INTO CONTACT WITH ELECTRICITY. DO NOT STORE AT TEMPERATURE EXCEEDING 93 °C (200 °F). REPLACE AIRBAG SYSTEM COMPONENTS ONLY WITH PARTS SPECIFIED IN THE CHRYSLER MOPAR PARTS CATALOG. SUBSTITUTE PARTS MAY APPEAR INTERCHANGEABLE, BUT INTERNAL DIFFERENCES MAY RESULT IN INFERIOR OCCUPANT PROTECTION. THE FASTENERS, SCREWS, AND BOLTS ORIGINALLY USED FOR THE AIRBAG SYSTEM COMPONENTS HAVE SPECIAL COATINGS AND ARE SPECIFICALLY DESIGNED FOR THE AIRBAG SYSTEM. THEY MUST NEVER BE REPLACED WITH ANY SUBSTITUTES. ANY TIME A NEW FASTENER IS NEEDED, REPLACE IT WITH THE CORRECT FASTENERS PROVIDED IN THE SERVICE PACKAGE OR SPECIFIED IN THE MOPAR PARTS CATALOG.