DTC Troubleshooting: B0072-1A

DTC B0072-1A: Decreased Resistance in the Front Passenger's Seat Belt Tensioner

Special Tools Required

SRS Short Canceller 070AZ-SAA0100

NOTE:

	Before doing this troubleshooting procedure, find out if the vehicle was in a collision. If so, verify that all the required components were replaced with new components of the correct part number, and that they were properly installed.
	Before doing this troubleshooting procedure, review SRS Precautions and Procedures, General Troubleshooting Information, and 12 Volt Battery Terminal Disconnection and Reconnection.
	Before replacing the SRS unit, check the SRS unit software version with the HDS. If the software version is not the latest, update the SRS unit software, and retest.

DTC Description	DTC
B0072-1A Decreased resistance in the front passenger's seat belt tensioner

Problem verification:

Problem verification

?1.	Clear the DTCs with the HDS.

?2.	Turn the vehicle to the ON mode, then wait for 10 seconds.

?3.

Check for DTCs with the HDS.

DTC Description	DTC
B0072-1A Decreased resistance in the front passenger's seat belt tensioner

Is DTC B0072-1A indicated?


	YES

The failure is duplicated. Go to step 2.


	NO

Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, troubleshoot the DTC.?

Front passenger's seat belt tensioner check:

Front passenger's seat belt tensioner check

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.

?3.	Remove the right side B-pillar lower trim.

?4.

Disconnect the following connector.

Front passenger's seat belt tensioner 2P connector (on the floor wire harness)

?5.	Reconnect the negative cable to the 12 volt battery.

?6.	Clear the DTCs with the HDS.

?7.	Turn the vehicle to the ON mode, then wait for 10 seconds.

?8.

Check for DTCs with the HDS.

DTC Description	DTC
B0072-1A Decreased resistance in the front passenger's seat belt tensioner

Is DTC B0072-1A indicated?


	YES

Go to step 3.


	NO

Short to another wire in the front passenger's seat belt tensioner; replace the front passenger's seat belt, then clear the DTC.?

Shorted wire check (RRP? line to RRP? line):

Shorted wire check (RRP? line to RRP? line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.	Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.

?3.

Disconnect the following connector.

SRS unit connector B (39P)

?4.	Connect the SRS short canceller to SRS unit connector B (39P) terminals No. 22 and No. 23.

?5.

Measure the resistance between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Front passenger's seat belt tensioner 2P connector (on the floor wire harness): disconnected
	SRS unit connector B (39P): disconnected
	SRS unit connector B (39P) No. 22 and No. 23: connected to SRS short canceller
Test point 1	SRS unit connector B (39P) No. 22
Test point 2	SRS unit connector B (39P) No. 23

Is there an open circuit, or at least 1 M??


	YES

The RRP? and RRP? wires are OK. Faulty SRS unit or poor connection at SRS unit connector B (39P) and the SRS unit. Check the connection; if the connection is OK, replace the SRS unit. If the DTC does not clear, replace the floor wire harness.?


	NO

Short to another wire in the floor wire harness; replace the floor wire harness, then clear the DTC.?