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Home >> Lincoln >> 2009 >> MKS FWD V6-3.7L >> Repair and Diagnosis >> Restraints and Safety Systems >> Air Bag Systems >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Test I: DTC B2290 >> I35-I50

I35-I50




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

Pinpoint Tests

Pinpoint Test I: DTC B2290

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

NOTE: DTC B2290 reported by the Restraints Control Module (RCM) is informational only and indicates the presence of a fault in the Occupant Classification System Module (OCSM). Refer to the Supplemental Restraint System (SRS) DTC Chart when DTC B2290 is reported by the RCM for diagnostic instructions. [1][2]Diagnostic Trouble Code Descriptions

NOTE: The following pinpoint test must only be used to diagnose DTC B2290 when reported by the OCSM.

Normal Operation

The Occupant Classification Sensor (OCS) system is used to classify the front passenger seat occupant in the event of a deployable impact. Refer to Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Description and Operation.

The OCSM monitors the 4 OCS weight sensor bolts and circuity for faults. If the OCSM detects a fault, it will store DTC B2290 in memory and send a message to the 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.

Normal Operation (Belt Tension Sensor (BTS))

The Belt Tension Sensor (BTS) operates in conjunction with the OCSM. The OCSM interprets a variable voltage signal provided by the BTS to identify the possible presence of a child safety seat in the front passenger seat. The voltage output of the BTS is proportional to the amount of tension applied to the sensor by the belt from no tension low voltage (approximately 0.95 volt) to high tension high voltage (approximately 3.8 volts).

The OCSM monitors the BTS and circuitry for faults. If the OCSM detects a fault, it will store DTC B2290 in memory and send a message to the RCM. The RCM will store DTC B2290 in memory and send a message to the instrument cluster to flash Lamp Fault Code (LFC) 16 on the air bag warning indicator. After the LFCs are displayed, the air bag warning indicator will remain illuminated for the rest of the ignition cycle.





a Fault PIDs that end in OD indicate an on-demand status and are associated with on-demand DTC B2290. Fault PIDs that end in CM indicate continuous memory status and are associated with continuous DTC B2290.

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



PINPOINT TEST I: DTC B2290

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

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I35 CHECK THE BTS 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 Seat Side Air Bag Module C3137.
- Disconnect: Passenger Safety Belt Buckle Switch C3066.
- Disconnect: Belt Tension Sensor C3238.
- Disconnect: OCSM C3159.
- 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.
- Measure the voltage between OCSM:
- C3159-11, circuit LR142 (YE/BU), harness side and ground.
- C3159-12, circuit VR210 (BU/BN), harness side and ground.




- Is voltage present on either circuit?

Yes
REPAIR the affected circuit. GO to I50.

No
GO to I36.

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I36 CHECK THE BTS 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.
- Measure the resistance between OCSM C3159, harness side and belt tension sensor C3238, harness side using the following chart.









- Are the resistances less than 0.5 ohm?

Yes
GO to I37.

No
REPAIR the affected circuit. GO to I50.

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I37 CHECK THE BTS CIRCUITS FOR A SHORT TO GROUND


- Measure the resistance between OCSM:
- C3159-11, circuit LR142 (YE/BU), harness side and ground.
- C3159-12, circuit VR210 (BU/BN), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to I38.

No
REPAIR the affected circuit. GO to I50.

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I38 CHECK FOR A SHORT BETWEEN BTS CIRCUITS


- Measure the resistance between OCSM C3159, harness side using the following chart.









- Are the resistances greater than 10,000 ohms?

Yes
GO to I39.

No
REPAIR circuit LR142 (YE/BU), GD901 (BK) or VR210 (BU/BN). GO to I50.

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I39 CHECK THE OCSM OUTPUT


- Connect: OCSM C3159.
- 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.
- Measure the voltage between BTS C3238-1, circuit LR142 (YE/BU), harness side and C3238-2, circuit GD901 (BK), harness side.




- Is voltage approximately 5 volts?

Yes
GO to I40.

No
INSTALL a new OCSM. REFER to Occupant Classification System Module (OCSM) Service and Repair. GO to I50.

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I40 CHECK THE BTS VOLTAGE OUTPUT


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Connect a fused jumper lead between BTS C3238 pin 1, circuit LR142 (YE/BU), harness side and pin 1, circuit LR142 (YE/BU), component side.
- Connect a fused jumper lead between BTS C3238 pin 2, circuit GD901 (BK), harness side and pin 2, circuit GD901 (BK), component side.
- 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.
- Measure the voltage between BTS C3238 pin 3, circuit VR210 (BU/BN), component side and ground as you vary the tension of the BTS.




- Does the voltage vary from approximately 0.95 volt with no tension applied to the sensor to approximately 3.8 volts with full tension applied to the sensor?

Yes
GO to I48.

No
INSTALL a new safety belt retractor. GO to I50.

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I41 CHECK THE BTS AND RETRIEVE OCSM DTCs


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: BTS C3238.
- 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 .
- Enter the following diagnostic mode on the scan tool: DataLogger - OCSM - View and Record The Following Fault PIDs.
- 2290_20_OD
- 2290_21_OD
- DIAGNOSTIC TIP: When viewing DTC B2290 on-demand fault PIDs with the BTS disconnected, a circuit fault would normally be retrieved.
- Did the on-demand PID change from 2290_20_OD to a 2290_21_OD?

Yes
INSTALL a new safety belt retractor assembly. GO to I50.

No
GO to I42.

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I42 CHECK THE BTS CIRCUIT 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 Seat Side Air Bag Module C3137.
- Disconnect: Passenger Safety Belt Buckle Switch C3066.
- Disconnect: OCSM C3159.
- 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.
- Measure the voltage between BTS C3238-1, circuit VR210 (BU/BN), harness side and ground.




- Is any voltage present?

Yes
REPAIR circuit VR210 (BU/BN). GO to I50.

No
GO to I43.

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I43 CHECK THE BTS 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.
- Measure the resistance between BTS
- C3238-1, circuit VR210 (BU/BN), harness side and ground.
- C3238-1, circuit VR210 (BU/BN), harness side and C3238-2, circuit GD901 (BK), harness side.




- Is the resistances greater than 10,000 ohms?

Yes
GO to I44.

No
REPAIR circuits VR210 (BU/BN) and GD901 (BK). GO to I50.

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I44 CHECK THE OCS WEIGHT SENSOR BOLT CIRCUITS FOR A SHORT TO GROUND


- Disconnect: OCS Weight Sensor Bolt C3324, C3325, C3330 and C3331.
- Measure the resistance between OCS weight sensor:
- bolt 1 C3324-1, circuit CR140 (YE/GN), harness side and ground
- bolt 2 C3325-1, circuit CR141 (BN/YE), harness side and ground
- bolt 3 C3330-1, circuit CR153 (GN/WH), harness side and ground
- bolt 4 C3331-1, circuit CR154 (VT/OG), harness side and ground




- Are the resistances greater than 10,000 ohms?

Yes
GO to I45.

No
REPAIR the affected circuit(s). GO to I50.

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I45 CHECK FOR A SHORT BETWEEN THE OCS WEIGHT SENSOR BOLT CIRCUITS


- Measure the resistance between OCS weight sensor bolt, harness side using the following chart:









- Are the resistances greater than 10,000 ohms?

Yes
GO to I46.

No
REPAIR circuits CR140 (YE/GN) and RR140 (GN/OG), CR141 (BN/YE) and RR141 (VT/BN), CR153 (GN/WH) and RR153 (GY/BU) or CR154 (VT/OG) and RR154 (VT/WH). GO to I50.

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I46 CHECK THE OCS WEIGHT SENSOR BOLT CIRCUITS FOR AN OPEN


- Measure the resistance between OCS weight sensor, harness side and OCSM C3159, harness side using the following chart:









- Are the resistances less than 5 ohms?

Yes
GO to I47.

No
REPAIR circuit CR140 (YE/GN), CR141 (BN/YE), CR153 (GN/WH) or CR154 (VT/OG). GO to I50.

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I47 CHECK OCS WEIGHT SENSOR BOLT(S) CIRCUITS FOR A SHORT TO VOLTAGE


- 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.
- Measure the voltage between OCS weight sensor:
- bolt 1 C3324-1, circuit CR140 (YE/GN), harness side and ground
- bolt 2 C3325-1, circuit CR141 (BN/YE), harness side and ground
- bolt 3 C3330-1, circuit CR153 (GN/WH), harness side and ground
- bolt 4 C3331-1, circuit CR154 (VT/OG), harness side and ground




- Is voltage present on any circuit?

Yes
REPAIR circuit CR140 (YE/GN), CR141 (BN/YE), CR153 (GN/WH) or CR154 (VT/OG). GO to I50.

No
GO to I48.

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I48 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, erroneous 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.
- Prior to reconnecting any previously disconnected SRS component:
- inspect connector(s) (including any in-line connectors) for pushed out, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- repair any concerns found. Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- Connect: OCSM C3159 (if previously disconnected).
- Connect: BTS C3238 (if previously disconnected).
- Connect: Affected OCS Weight Sensor Bolt Electrical Connector(s) (if previously disconnected).
- 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 .
- Enter the following diagnostic mode on the scan tool: DataLogger - OCSM - View and Record All 2290 Fault PIDs.
- Refer to PID list in Normal Operation to view 2290 fault PIDs.
- Does the original on-demand 2290 fault PID indicate a fault?

Yes
INSTALL a new OCSM. REFER to Occupant Classification System Module (OCSM) Service and Repair. GO to I50.

No
In the process of diagnosing the fault, the fault condition has become intermittent. 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. GO to I49.

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I49 CHECK FOR AN INTERMITTENT FAULT


- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect the affected OCS Weight Sensor Bolt:
- inspect connector(s) (including any in-line 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.
- repair any concerns found. Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- Connect: All Previously Disconnected Component(s)/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 .
- Enter the following diagnostic mode on the scan tool: DataLogger - OCSM - View and Record All 2290 Fault PIDs.
- Refer to PID list in Normal Operation to view 2290 fault PIDs.
- Do any on-demand 2290 fault PIDs indicate a fault?

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.

Using the fault PIDs recorded, GO to the appropriate pinpoint test step.

For 2290_3_OD, 2290_7_OD, 2290_11_OD or 2290_15_OD, INSTALL a new seat track.

For 2290_14_OD, GO to I3.

For 2290_13_OD, GO to I7.

For 2290_12_OD, GO to I9.

For 2290_10_OD, GO to I11.

For 2290_9_OD, GO to I15.

For 2290_8_OD, GO to I17.

For 2290_6_OD, GO to I19.

For 2290_5_OD, GO to I23.

For 2290_4_OD, GO to I25.

For 2290_2_OD, GO to I27.

For 2290_1_OD, GO to I31.

For 2290_0_OD, GO to I33.

For 2290_21_OD, GO to I35.

For 2290_20_OD, GO to I41.

No
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 I50.

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I50 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.
- 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 on-demand during self-test?

Yes
Do not clear any DTCs until all DTCs have been resolved. GO to the DTC Charts for pinpoint test direction. [1][2]Diagnostic Trouble Code Descriptions

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

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