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Part 2




Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)

Pinpoint Tests

Pinpoint Test B: DTC B1085

Refer to Wiring Diagram Set 46, Supplemental Restraint System for schematic and connector information. Diagrams By Number

Normal Operation

The Restraints Control Module (RCM) continuously monitors the adaptive load limiting retractors circuits for an acceptable resistance range, unacceptable voltage and shorts to ground. The RCM will set and store on-demand DTC B1085 in memory if any of these conditions are detected. If the RCM detects a fault, it will send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

As the RCM continuously monitors adaptive load limiting retractor circuits for resistance, it expects a normal resistance between 1.31 and 4.29 ohms.

If a loop resistance is between 0.9 and 1.31 ohms or between 4.29 and 5 ohms, there exists a strong potential for an intermittent fault, a DTC may or may not set. The RCM will also set an on-demand DTC if the loop resistance is less than 0.9 ohm or greater than 5 ohms.

NOTE: When monitoring fault and/or resistance PIDs with the scan tool, it may take up to 2 seconds for the scan tool display to update.





a Fault PIDs that end in OD indicate an on-demand status and are associated with on-demand DTC B1085. Fault PIDs that end in CM indicate continuous memory status and are associated with continuous DTC B1085.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Adaptive load limiting retractor
- RCM



PINPOINT TEST B: DTC B1085

WARNING: Do not handle, move or change the original horizontal mounting position of the restraints control module (RCM) while the RCM is connected and the ignition switch is ON. Failure to follow this instruction may result in the accidental deployment of the Safety Canopy(R) and cause serious personal injury or death.

WARNING: Never disassemble or tamper with safety belt buckle/retractor pretensioners or adaptive load limiting retractors or probe the electrical connectors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors which increases the risk of serious personal injury or death.

NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when taking measurements. Failure to use the correct probe adapter(s) may damage the connector.

Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test. Inspection and Verification

NOTE: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.

NOTE: SRS components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.


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B14 CHECK FOR A SHORT BETWEEN PASSENGER ADAPTIVE LOAD LIMITING RETRACTOR CIRCUITS


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310a and C310b.
- Measure resistance between passenger adaptive load limiting retractor C303-1, circuit CR147 (GN/OG), harness side and C303-2, circuit RR147 (YE/VT), harness side.




- Is resistance greater than 10,000 ohms?

Yes
GO to B21.

No
REPAIR circuits CR147 (GN/OG) and RR147 (YE/VT). GO to B26.

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B15 CHECK THE PASSENGER ADAPTIVE LOAD LIMITING RETRACTOR FAULT PIDs (1085_25_OD) AND (1085_24_OD) FOR A CHANGE IN FAULT STATUS


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Adaptive Load Limiting Retractor C303.
- Connect a fused jumper wire between passenger adaptive load limiting retractor C303-1, circuit CR147 (GN/OG), harness side and C303-2, circuit RR147 (YE/VT), harness side.
- Repower the SRS. Do not prove out the system at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 1085_24_OD (Seatbelt Load Limiter Front Passenger Circuit Resist Low on Squib)
- 1085_25_OD (Seatbelt Load Limiter Front Passenger Open)
- DIAGNOSTIC TIP: When viewing DTC B1085 on-demand fault PIDs with the passenger adaptive load limiting retractor circuits shorted together, a low resistance fault would normally be retrieved.
- Did the passenger adaptive load limiting retractor on-demand fault PIDs change from indicating an open circuit to a low resistance fault?

Yes
GO to B20.

No
GO to B16.

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B16 CHECK PASSENGER ADAPTIVE LOAD LIMITING RETRACTOR CIRCUITS FOR AN OPEN


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Remove the jumper wire from passenger adaptive load limiting retractor C303.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310b-38, circuit CR147 (GN/OG), harness side and passenger adaptive load limiting retractor C303-1, circuit CR147 (GN/OG), harness side.




- Measure resistance between RCM C310b-37, circuit RR147 (YE/VT), harness side and passenger adaptive load limiting retractor C303-2, circuit RR147 (YE/VT), harness side.




- Are resistances less than 0.5 ohm?

Yes
GO to B21.

No
REPAIR circuit RR147 (YE/VT) or RR147 (YE/VT). GO to B26.

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B17 CHECK THE PASSENGER ADAPTIVE LOAD LIMITING RETRACTOR FAULT PIDs (1085_27_OD) AND (1085_25_OD) FOR A CHANGE IN FAULT STATUS


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Adaptive Load Limiting Retractor C303.
- Repower the SRS. Do not prove out the system at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 1085_27_OD (Seatbelt Load Limiter Front Passenger Short to Ground)
- 1085_25_OD (Seatbelt Load Limiter Front Passenger Open)
- DIAGNOSTIC TIP: When viewing DTC B1085 on-demand fault PIDs with the passenger adaptive load limiting retractor disconnected, an open circuit fault would normally be retrieved.
- Did the passenger adaptive load limiting retractor on-demand fault PIDs change from indicating a short to ground to an open circuit fault?

Yes
GO to B20.

No
GO to B18.

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B18 CHECK PASSENGER ADAPTIVE LOAD LIMITING RETRACTOR CIRCUITS FOR A SHORT TO GROUND


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310a and C310b.
- Measure resistance between passenger adaptive load limiting retractor:
- C303-2, circuit RR147 (YE/VT), harness side and ground.
- C303-1, circuit CR147 (GN/OG), harness side and ground.




- Are resistances greater than 10,000 ohms?

Yes
GO to B21.

No
REPAIR circuit RR147 (YE/VT) or CR147 (GN/OG). GO to B26.

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B19 CHECK PASSENGER ADAPTIVE LOAD LIMITING RETRACTOR CIRCUITS FOR A SHORT TO VOLTAGE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Adaptive Load Limiting Retractor C303.
- Disconnect: RCM C310a and C310b.
- Repower the SRS. Do not prove out the system at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Measure voltage between passenger adaptive load limiting retractor:
- C303-2, circuit RR147 (YE/VT), harness side and ground.
- C303-1, circuit CR147 (GN/OG), harness side and ground.




- Is voltage present on either circuit?

Yes
REPAIR circuit RR147 (YE/VT) or CR147 (GN/OG). GO to B26.

No
GO to B21.

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B20 CONFIRM THE ADAPTIVE LOAD LIMITING RETRACTOR FAULT


NOTE: Make sure all restraint system components, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the on-demand self test. If not, DTCs will be recorded.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Connect: Affected Adaptive Load Limiting Retractor C323 (Driver) C303 (Passenger).
- Repower the SRS. Do not prove out the system at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record All 1085 Fault PIDs.
- Refer to PID list in Normal Operation to view 1085 fault PIDs.
- Does the original RCM on-demand 1085 fault PID indicate a fault?

Yes
INSTALL a new driver or passenger adaptive load limiting retractor. REFER to Restraint Systems. GO to B26.

No
In the process of diagnosing the fault, the fault condition has become intermittent. Using the fault PIDs recorded, GO to the appropriate pinpoint test step and CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of electrical connectors that were disconnected.

For 1085_28_CM (Seatbelt Load Limiter Driver Circuit Resist Low on Squib), 1085_24_CM (Seatbelt Load Limiter Front Passenger Circuit Resist Low on Squib), 1085_29_CM (Seatbelt Load Limiter Driver Open)
and 1085_25_CM (Seatbelt Load Limiter Front Passenger Open), GO to B22.

For 1085_31_CM (Seatbelt Load Limiter Driver Short to Ground) and 1085_27_CM (Seatbelt Load Limiter Front Passenger Short to Ground), GO to B24.

For 1085_30_CM (Seatbelt Load Limiter Driver Short to Battery) and 1085_26_CM (Seatbelt Load Limiter Front Passenger Short to Battery), GO to B25.

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B21 CONFIRM THE RCM FAULT


NOTE: Make sure all restraint system components, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the on-demand self test. If not, DTCs will be recorded.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Connect: All Restraint System Components (if previously disconnected).
- Connect: RCM C310a and C310b (if previously disconnected).
- Repower the SRS. Do not prove out the system at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record All 1085 Fault PIDs.
- Refer to PID list in Normal Operation to view 1085 fault PIDs.
- Does the original RCM on-demand 1085 fault PID indicate a fault?

Yes
INSTALL a new RCM. REFER to Restraints Control Module (RCM) Service and Repair. GO to B26.

No
In the process of diagnosing the fault, the fault condition has become intermittent. Using the fault PIDs recorded, GO to the appropriate pinpoint test step and CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of electrical connectors that were disconnected.

For 1085_28_CM (Seatbelt Load Limiter Driver Circuit Resist Low on Squib), 1085_24_CM (Seatbelt Load Limiter Front Passenger Circuit Resist Low on Squib), 1085_29_CM (Seatbelt Load Limiter Driver Open)
and 1085_25_CM (Seatbelt Load Limiter Front Passenger Open), GO to B22.

For 1085_31_CM (Seatbelt Load Limiter Driver Short to Ground) and 1085_27_CM (Seatbelt Load Limiter Front Passenger Short to Ground), GO to B24.

For 1085_30_CM (Seatbelt Load Limiter Driver Short to Battery) and 1085_26_CM (Seatbelt Load Limiter Front Passenger Short to Battery), GO to B25.

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B22 CHECK ADAPTIVE LOAD LIMITING RETRACTOR PRETENSIONER RESISTANCE PIDs FOR AN INTERMITTENT LOW RESISTANCE OR OPEN


- If the fault was reported for the driver adaptive load limiting retractor, monitor the D_LOAD (Seatbelt Load Limiter Resistance, Driver Side) resistance PID.
- If the fault was reported for the passenger adaptive load limiting retractor, monitor the P_LOAD (Seatbelt Load Limiter Resistance, Passenger Side) pretensioner resistance PID.
- NOTE: A resistance PID that reads between 0.9 and 1.31 ohms or between 4.29 and 5 ohms may or may not set an on-demand DTC yet indicates a strong potential of an intermittent fault condition. Make sure to thoroughly check wire harness(es), connectors and terminals as they are the likely source of the fault condition.
- Attempt to recreate the fault by wiggling the connectors (including any inline connectors) and flexing the wire harness.
- Does any adaptive load limiting retractor resistance PID indicate less than 1.31 ohms or greater than 4.29 ohms?

Yes
DEPOWER the SRS and REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

GO to B26.

No
GO to B23.

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B23 CHECK THE HARNESS AND CONNECTORS


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect the affected adaptive load limiting retractor C323 (driver) or C303 (passenger):
- inspect connector(s) (including any inline connectors) for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- Were any concerns found?

Yes
REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

GO to B26.

No
The fault is not present and cannot be recreated at this time.

CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition frequently. ACTIVATE other systems in the same wire harness. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. REPAIR any intermittent wiring, terminal or connector concerns found. GO to B26.

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B24 CHECK ADAPTIVE LOAD LIMITING RETRACTOR FAULT PIDs FOR AN INTERMITTENT SHORT TO GROUND


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - PID.
- If the fault was reported for the driver adaptive load limiting retractor, monitor the 1085_31_OD (Seatbelt Load Limiter Driver Short to Ground) on-demand fault PID on the scan tool.
- If the fault was reported for the passenger adaptive load limiting retractor, monitor the 1085_27_OD (Seatbelt Load Limiter Front Passenger Short to Ground) on-demand fault PID on the scan tool.
- DIAGNOSTIC TIP: When monitoring fault PIDs with the scan tool, it may take up to 2 seconds for the scan tool display to update.
- Attempt to recreate the fault by wiggling connectors (including any inline connectors) and flexing the wire harness.
- Does any adaptive load limiting retractor on-demand fault PID indicate a fault is present?

Yes
DEPOWER the SRS and REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

GO to B26.

No
The fault is not present and cannot be recreated at this time.

CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition frequently. ACTIVATE other systems in the same wire harness. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. REPAIR any intermittent wiring, terminal or connector concerns found. GO to B26.

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B25 CHECK ADAPTIVE LOAD LIMITING RETRACTOR FAULT PIDs FOR AN INTERMITTENT SHORT TO VOLTAGE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect the side air bag module electrical connector C3049 (driver) or C3050 (passenger) on the side with the affected pretensioner.
- Repower the SRS. Do not prove out the system at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- If the fault was reported for the driver adaptive load limiting retractor , monitor the 1085_30_OD (Seatbelt Load Limiter Driver Short to Battery) on-demand fault PID.
- If the fault was reported for the passenger adaptive load limiting retractor, monitor the 1085_26_OD (Seatbelt Load Limiter Front Passenger Short to Battery) on-demand fault PID.
- DIAGNOSTIC TIP: When monitoring fault PIDs with the scan tool, it may take up to 2 seconds for the scan tool display to update.
- Attempt to recreate the fault by wiggling the connectors (including any inline connectors) and flexing the wire harness.
- Does the adaptive load limiting retractor short to battery on-demand fault PID indicate a fault is present?

Yes
DEPOWER the SRS and REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

GO to B26.

No
The fault is not present and cannot be recreated at this time.

CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition frequently. ACTIVATE other systems in the same wire harness. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. REPAIR any intermittent wiring, terminal or connector concerns found. GO to B26.

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B26 CHECK FOR ADDITIONAL SRS DTCs


- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Reconnect all SRS components (if previously disconnected).
- If previously directed to depower the SRS, repower the SRS. Do notprove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - Restraints.
- Are any RCM and/or OCSM DTCs indicating a fault?

Yes
Do not clear any DTCs until all DTCs have been resolved. GO to the DTC Charts for pinpoint test direction. Diagnostic Trouble Code Tests and Associated Procedures

No
CLEAR all RCM and OCSM CMDTCs. PROVE OUT the SRS. Repair is complete. RETURN the vehicle to the customer.

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