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Pinpoint Test O: DTC B2433




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

Pinpoint Tests

Pinpoint Test O: DTC B2433

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

Lamp Fault Codes (LFCs)

The following Lamp Fault Code (LFC) indicates the specific fault associated with DTC B2433:

- LFC 7-9 - Driver Seat Belt Buckle Switch Circuit Short to Battery

Normal Operation

The safety belt buckles are equipped with Hall-effect switches. The safety belt buckle switches indicate to the Restraints Control Module (RCM) whether the safety belts are buckled or unbuckled.

The RCM checks the driver safety belt buckle switch circuits for faults. If the RCM detects a short to battery fault, it will store DTC B2433 in memory, flash LFC 7-9 on the air bag warning indicator.

- DTC B2433 (Drivers Seat Belt Buckle Switch Short to Battery) - If the RCM detects a short to voltage on the driver safety belt buckle circuit, it will set this DTC.

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

PINPOINT TEST O: DTC B2433

WARNING: Remove restraint system diagnostic tools from the vehicle prior to road testing. If tools are not removed, the supplemental restraint system (SRS) device may not deploy in a crash. Failure to follow this instruction may result in serious personal injury or death in a crash and possibly violate vehicle safety standards.

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.

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

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.

NOTE: 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

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O1 RETRIEVE SRS DTCs


- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Was DTC B2433 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 on-demand during self test. GO to O2.

No
This is an intermittent fault when present as a CMDTC only (DTC not retrieved on demand). The fault condition is not present at this time. GO to O5.

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O2 CHECK CIRCUITS 85 (BN/LB) AND 1558 (TN/BK) 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: Driver Seat Side Air Bag Module C315.
- Connect: Restraint System Diagnostic Tool 418-133 to Driver Seat Side Air Bag Module C315 .
- Disconnect: RCM C310a and C310b.
- Disconnect: Driver Safety Belt Buckle Switch C3065.
- 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 driver safety belt buckle switch C3065-1, circuit 85 (BN/LB), harness side and ground; and between driver safety belt buckle switch C3065-2, circuit 1558 (TN/BK), harness side and ground.




- Is voltage present on either circuit?

Yes
REPAIR circuit 85 (BN/LB) or 1558 (TN/BK). GO to O6.

No
GO to O3.

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O3 CHECK THE DRIVER SAFETY BELT BUCKLE SWITCH


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Connect: RCM C310a and C310b.
- Install a known good driver safety belt buckle. Refer to Safety Belt System Safety Belt Buckle - Front.
- 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 - RCM.
- Was DTC B2433 retrieved on-demand during self-test?

Yes
GO to O4.

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, terminals or connector concerns found. GO to O6.

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O4 CONFIRM THE RCM FAULT


NOTE: Make sure all restraint system diagnostic tools, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the 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.
- Reinstall the original driver safety belt buckle.
- 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 - RCM.
- Was DTC B2433 retrieved on-demand during self-test?

Yes
INSTALL a new RCM. REFER to Restraints Control Module (RCM) Service and Repair. GO to O6.

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, terminals or connector concerns found. GO to O6.

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O5 CHECK FOR AN INTERMITTENT FAULT


- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Was DTC B2433 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 on-demand during self test. GO to O2.

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, terminals or connector concerns found. GO to O6.

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O6 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 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 - RCM.
- Are any DTCs retrieved on-demand during self-test?

Yes
Do not clear any DTCs until all DTCs have been resolved. GO to the Supplemental Restraint System (SRS) DTC Chart for pinpoint test direction. Supplemental Restraint System (SRS) DTC Chart

No
CLEAR all CMDTCs. PROVE OUT the SRS. REPAIR is complete. RETURN the vehicle to the customer.

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