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Pinpoint Test AB: DTC U200D:12




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

Pinpoint Tests - Occupant Classification System Module (OCSM)

Pinpoint Test AB: DTC U200D:12

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

Normal Operation

The Occupant Classification System Module (OCSM) monitors each Occupant Classification Sensor (OCS) weight sensor bolt and circuitry for faults. If the OCSM detects unwanted voltage on any weight sensor feed circuit it will store DTC U200D:12 in memory and send a message to the Restraints Control Module (RCM).

The RCM will store DTC B2290 in memory and send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

- DTC U200D:12 Control Module Output Power A: Circuit Short to Battery - If the OCSM detects unwanted voltage on any of the weight sensor feed circuits, it will set this DTC.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- OCSM



PINPOINT TEST AB: DTC U200D:12

WARNING: Never probe the electrical connectors on air bag, Safety Canopy(R) or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.

WARNING: Never probe the electrical connectors on safety belt buckle/retractor pretensioners or adaptive load limiting retractors. 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 making 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: Supplemental Restraint System (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.

NOTE: Do not install any new OCS system components until directed to do so. OCS system components should only be installed when directed to do so in the pinpoint test.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

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AB1 RETRIEVE OCSM DTCs


- Enter the following diagnostic mode on the scan tool: Self Test - OCSM.
- Was DTC U200D:12 retrieved on-demand during self-test?

Yes
The fault condition is still present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to AB2.

No
This is an intermittent fault when present as a continuous memory DTC only. The fault condition is not present at this time. GO to AB7.

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AB2 CHECK THE SEAT WIRING AND CONNECTORS


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Carry out a thorough visual inspection of the OCS system wiring, terminals and connectors, jumper harness, weight sensor bolt connector and connection, wiring harness routing and the related seat wiring harness and body wiring harness terminals and connectors.
- Were any problems noted?

Yes
REPAIR the seat connectors and wiring as needed.
Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to AB8.

No
GO to AB3.

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AB3 CHECK INBOARD OCS WEIGHT SENSOR BOLT JUMPER HARNESS FOR SHORT TO VOLTAGE AND RETRIEVE OCSM DTCs


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

- Disconnect: Seat Harness C3136.
- Repower the SRS. Do not prove 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 - OCSM.
- DIAGNOSTIC TIP: When viewing on-demand DTCs with the seat harness C3136 disconnected, numerous sensor circuit faults would normally be retrieved.
- Was DTC U200D:12 retrieved on-demand during self-test?

Yes
GO to AB4.

No
REMOVE and INSPECT the inboard OCS weight sensor jumper harness, connectors and terminals for damage. REFER to Occupant Classification Sensor Service and Repair. If a concern is found, REPAIR or INSTALL a new jumper harness. GO to AB8.

If a concern was not found, INSTALL a new OCS left (inboard) weight sensor assembly. GO to AB8.

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AB4 CHECK OUTBOARD OCS WEIGHT SENSOR BOLT JUMPER HARNESS FOR SHORT TO VOLTAGE AND RETRIEVE OCSM DTCs


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

- Disconnect: Seat Harness C3135.
- Repower the SRS. Do not prove 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 - OCSM.
- DIAGNOSTIC TIP: When viewing on-demand DTCs with the seat harness C3136 and C3135 disconnected, numerous sensor circuit faults would normally be retrieved.
- Was DTC U200D:12 retrieved on-demand during self-test?

Yes
GO to AB5.

No
REMOVE and INSPECT the outboard OCS weight sensor jumper harness, connectors and terminals for damage. REFER to Occupant Classification Sensor Service and Repair. If a concern is found, REPAIR or INSTALL a new jumper harness. GO to AB8.

If a concern was not found, INSTALL a new OCS right (outboard) weight sensor assembly. GO to AB8.

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AB5 CHECK WEIGHT SENSOR FEED CIRCUITS FOR A SHORT TO VOLTAGE


- Disconnect: OCSM C3159.
- Measure voltage between a good ground and the following circuits using the chart below:









- Is voltage present on any circuit?

Yes
REPAIR the affected circuits. GO to AB8.

No
GO to AB6.

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AB6 CONFIRM THE OCSM FAULT


NOTE: Make sure all restraint system sensor electrical connectors and the RCM electrical connector 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: OCSM C3159 (if previously disconnected).
- Connect: Seat Harness Electrical Connector(s).
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Enter the following diagnostic mode on the scan tool: Self Test - OCSM.
- Was DTC U200D:12 retrieved on-demand during self-test?

Yes
INSTALL a new OCSM. REFER to Occupant Classification System Module (OCSM) Service and Repair. GO to AB8.

No
In the process of diagnosing the fault, the fault condition has become intermittent. CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of any electrical connector that were disconnected. 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 AB8.

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AB7 CHECK FOR AN INTERMITTENT FAULT


- Enter the following diagnostic mode on the scan tool: Self Test - OCSM.
- Was DTC U200D:12 retrieved on-demand during self-test?

Yes
The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test.

GO to AB2.

No
CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key 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.
Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to AB8.

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AB8 CHECK FOR ADDITIONAL 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.
- NOTE: When selecting Restraints from the Self Test menu, DTCs will be retrieved from the RCM and OCSM.
- Are any RCM and/or OCSM DTCs retrieved 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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