Restraint > SRSCM > Troubleshooting > B1334 FIS(Front Impact Sensor)-Passenger Communication error

General Description

Front Impact Sensor(FIS)located at both sides of the front of engine room detects head-on collision. When FIS delivers collision signal to SRSCM, SRSCM checks if safing sensor located in SRSCM detects collusion. And if both FIS and safing sensor detects collision simultaneously, SRSCM operates front air bag.

DTC Description

The SRSCM sets DTC B1334 if there is any error in communication between PFIS and SRSCM.

DTC Detecting Condition

Item

Detecting Condition

Possible cause

DTC Strategy

•	Check current(PWM type)

•	Poor connection of connected part.

•	Faulty FIS.

•	Faulty SRSCM.

Enable Conditions

•	Ignition "ON"

Diagnostic
Time

Qualification

•	More than 0 ~ 0.11 sec

De-Qualification

•	More than 0 ~ 1.5 sec

Schematic Diagram

Monitor Scantool Data

1.	Ignition "OFF", connect scantool.

2.	Ignition "ON"& Engine "OFF", select "Diagnostic Trouble Codes(DTC)" mode.

3.	Monitor diagnostic trouble code and present of trouble code.

4.	Using a scantool, clear the DTC.

Is DTC present problem ?

▶ Go to "W/Harness Inspection" procedure.

▶ Displaying nothing(no DTC) or DTC with label "H"(historical) shows that Fault is intermittent caused by poor contact in the part's and/or SRSCM connector or was repaired and SRSCM memory was not cleared.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
▶ Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

Terminal and Connector Inspection

1.	Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

2.	Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

	▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
	▶ Go to "Component inspection" procedure.

Component Inspection

1.	Ignition "ON" & Engine "OFF" and Using a scantool, clear the DTC.

2.	Ignition "OFF".

3.	Disconnect the battery (-) terminal cable from the battery, and wait at least one minutes.

4.	Disconnect FIS connector .

5.	Substitute the FIS and check for proper operation.

Is DTC present problem ?

	▶ Substitute a known-good SRSCM, and check for proper operation. If the problem is corrected, replace SRSCM and then go to "Verification of Vehicle Repair" procedure. ▶ Substitute the SRS main harness, and check for proper operation. If the problem is corrected, replace SRS main harness and then go to "Verification of Vehicle Repair" procedure.
	▶ Substitute a known-good FIS, and check for proper operation. If the problem is corrected, replace FIS and then go to "Verification of Vehicle Repair" procedure.

Verification of Vehicle Repair

After a repair, it is essential to verify that the fault has been corrected.

1.	Connect scantool and select "Diagnostic Trouble Codes(DTC)" mode.

2.	Using a scantool, clear the DTC.

3.	Operate the vehicle within DTC Enable conditions in General information.

Are any DTC present ?

	▶ Go to the applicable troubleshooting procedure.
	▶ System is performing to specification at this time.