Pinpoint Test C: DTC B29A4
Fire Suppression System
Pinpoint Tests
Pinpoint Test C: DTC B29A4
Refer to Wiring Diagram Set 96, Police Option for schematic and connector information. Diagrams By Number
Normal Operation
The Fire Suppression System Module (FSSM) monitors the RH fire suppression activation circuits for faults. If the FSSM detects an open on the RH fire suppression activation loop 1 circuits, it stores DTC B29A4 in memory and illuminates the Fire Suppression Indicator Lamp (FSIL).
- DTC B29A4 (Suppressor Right Circuit Open - Loop #1) - sets when the FSSM detects an open on the RH fire suppression activation loop 1 circuits. This DTC causes the FSIL to illuminate.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- RH fire suppressor/RH external fire suppressor actuator (if equipped)
- FSSM
PINPOINT TEST C: DTC B29A4
WARNING: To reduce the risk of accidental deployment, never probe the connectors on the fire suppressors. Failure to follow this instruction may cause unintentional deployment of the suppressors, which may result in serious personal injury.
WARNING: To prevent inadvertent deployment of the fire suppression system (FSS), do not defeat, cut or remove wiring connector shorting bars, including when servicing or removing the system. These wiring connectors incorporate shorting bars to reduce the potential for unintended suppressor activation from static electricity charges. Failure to follow this warning may result in serious personal injury or death.
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
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
NOTE: The fire suppression system must be fully operational and free of faults before releasing the vehicle to the customer.
NOTE: Failure to disconnect the battery when instructed results in false resistance readings. Refer to Battery, Mounting and Cables Battery Disconnect.
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C1 CHECK THE FSSM DTCs FROM THE SELF-TEST
- Check the recorded results from the FSSM self-test.
- Was DTC B29A4 retrieved on-demand during self-test?
Yes
GO to C2.
No
This is an intermittent fault when present as a Continuous Memory Diagnostic Trouble Code (CMDTC) only. GO to C5.
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C2 CHECK THE RH FIRE SUPPRESSION ACTIVATION CIRCUITS FOR A FAULT STATUS CHANGE (OPEN INDICATED)
- Ignition OFF.
- WARNING: To reduce the risk of accidental deployment, do not use any memory saver devices when depowering the fire suppression system. Failure to follow this instruction may result in serious personal injury.
- Depower the fire suppression system. Refer to Fire Suppression System Depowering and Repowering Procedures.
- Disconnect: RH Fire Suppressor C4316.
- Connect: Fire Suppression System Diagnostic Tool 501-117 to C4316, Harness Side..
- Repower the fire suppression system. Do not prove out the fire suppression system at this time. Refer to Fire Suppression System Depowering and Repowering Procedures.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test - FSSM.
- NOTE: When viewing DTCs with the fire suppression system diagnostic tool 501-117 installed, low resistance DTCs B29A8 and B29AD are expected to be retrieved when the self-test is carried out. These DTCs can be cleared once the tool is removed and all fire suppression connections are restored.
- Was DTC B29A4 retrieved on-demand during self-test?
Yes
GO to C3.
No
For vehicles with external fire suppressor actuators, INSTALL a new external RH fire suppressor actuator. REFER to Fire Suppressor - With External Fire Suppressor Actuator Fire Suppressor - With External Fire Suppressor Actuator.
For vehicles without external fire suppressor, INSTALL a new RH fire suppressor. REFER to Fire Suppressor - Without External Fire Suppressor Actuator Fire Suppressor - Without External Fire Suppressor Actuator.
CLEAR the DTCs. REPEAT the self-test. GO to C6.
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C3 CHECK THE RH FIRE SUPPRESSION ACTIVATION LOOP 1 CIRCUITS FOR AN OPEN
- Ignition OFF.
- WARNING: To reduce the risk of accidental deployment, do not use any memory saver devices when depowering the fire suppression system. Failure to follow this instruction may result in serious personal injury.
- Depower the fire suppression system. Refer to Fire Suppression System Depowering and Repowering Procedures.
- Disconnect: FSSM C3281A.
- Disconnect: Fire Suppression System Diagnostic Tool 501-117.
- Measure the resistance between the FSSM C3281A-12, circuit 2310 (OG), harness side and C4316-1, circuit 2310 (OG), harness side.
- Measure the resistance between the FSSM C3281A-13, circuit 2311 (DG), harness side and C4316-2, circuit 2311 (DG), harness side.
- Are the resistances less than 5 ohms?
Yes
GO to C4.
No
INSTALL an new wiring harness. CLEAR the DTCs. REPEAT the self-test. GO to C6.
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C4 CHECK FOR CORRECT FSSM OPERATION
- Disconnect all the FSSM connectors.
- Check for the following:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the FSSM connectors and make sure they seat correctly.
- Connect: All previously disconnected FSSM component(s)/connector(s) and make sure they seat correctly.
- Repower the fire suppression system. Do not prove out the fire suppression system at this time. Refer to Fire Suppression System Depowering and Repowering Procedures.
- Enter the following diagnostic mode on the scan tool: Self-Test - FSSM.
- Was DTC B29A4 retrieved on-demand during self-test?
Yes
INSTALL a new FSSM. REFER to Fire Suppression System Module (FSSM) Service and Repair. CLEAR the DTCs. REPEAT the self-test. GO to C6.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. GO to C6.
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C5 CHECK FOR AN INTERMITTENT FAULT
- Ignition OFF.
- WARNING: To reduce the risk of accidental deployment, do not use any memory saver devices when depowering the fire suppression system. Failure to follow this instruction may result in serious personal injury.
- Depower the fire suppression system. Refer to Fire Suppression System Depowering and Repowering Procedures.
- Inspect the FSSM and accessible fire suppression system wiring for the following:
- connectors for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
- wire harnesses for any damage, pinched, cut or pierced wires.
- Connect: All previously disconnected component(s)/connector(s) and make sure they seat correctly.
- Repower the fire suppression system. Do not prove out the fire suppression system at this time. Refer to Fire Suppression System Depowering and Repowering Procedures.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test - FSSM.
- Was DTC B29A4 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 the self-test. GO to C2.
No
The fault is not present and cannot be recreated at this time. CLEAR the DTCs. REPEAT the self-test. GO to C6.
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C6 CHECK FOR ADDITIONAL FIRE SUPPRESSION SYSTEM 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.
- Connect: All previously disconnected FSSM component(s)/connector(s) and make sure they seat correctly.
- If previously directed to depower the fire suppression system, repower the fire suppression system. Do not prove out the fire suppression system at this time. Refer to Fire Suppression System Depowering and Repowering Procedures
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test - FSSM.
- Are any FSSM 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. Diagnostic Trouble Code Tests and Associated Procedures
No
CLEAR all FSSM DTCs. PROVE OUT the fire suppression system. The repair is complete. RETURN the vehicle to the customer.
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