SRS DTC Troubleshooting: 81-54

DTC 81-54: Short to Power in the Front Passenger's Weight Sensor Power Circuit

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 and General Troubleshooting Information.

DTC Description	DTC
81-54 Short to power in the front passenger's weight sensor power circuit

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
81-54 Short to power in the front passenger's weight sensor power circuit

Is DTC 81-54 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.?

Shorted wire check (SWSP1 line to power):

Shorted wire check (SWSP1 line to power)

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

?2.

Disconnect the following connectors.

Front passenger's weight sensor unit connector A (6P)

Front passenger's weight sensor unit connector B (6P)

Front passenger's weight sensor unit connector C (6P)

?3.	Disconnect the front passenger's weight sensor (front inner side) 3P connector (A) on the front passenger's seat wire harness.

?4.	Turn the vehicle to the ON mode.

?5.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	Front passenger's weight sensor unit connector A (6P): disconnected
	Front passenger's weight sensor unit connector B (6P): disconnected
	Front passenger's weight sensor unit connector C (6P): disconnected
	Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness): disconnected
Test point 1	Front passenger's weight sensor (front inner side) 3P connector No. 1 (on the front passenger's seat wire harness)
Test point 2	Body ground

Is there about 5 V or more?


	YES

Short to power in the front passenger's seat wire harness; replace the front passenger's seat wire harness, then clear the DTC.?


	NO

The SWSP1 wire is OK. Go to step 3.

Shorted wire check (SWSP2 line to power):

Shorted wire check (SWSP2 line to power)

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

?2.	Disconnect the front passenger's weight sensor (rear inner side) 3P connector (A) on the front passenger's seat wire harness.

?3.	Turn the vehicle to the ON mode.

?4.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	Front passenger's weight sensor unit connector A (6P): disconnected
	Front passenger's weight sensor unit connector B (6P): disconnected
	Front passenger's weight sensor unit connector C (6P): disconnected
	Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness): disconnected
	Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness): disconnected
Test point 1	Front passenger's weight sensor (rear inner side) 3P connector No. 1 (on the front passenger's seat wire harness)
Test point 2	Body ground

Is there about 5 V or more?


	YES

Short to power in the front passenger's seat wire harness; replace the front passenger's seat wire harness, then clear the DTC.?


	NO

The SWSP2 wire is OK. Go to step 4.

Shorted wire check (SWSP3 line to power):

Shorted wire check (SWSP3 line to power)

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

?2.	Disconnect the front passenger's weight sensor (front outer side) 3P connector (A) on the front passenger's seat wire harness.

?3.	Turn the vehicle to the ON mode.

?4.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	Front passenger's weight sensor unit connector A (6P): disconnected
	Front passenger's weight sensor unit connector B (6P): disconnected
	Front passenger's weight sensor unit connector C (6P): disconnected
	Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness): disconnected
	Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness): disconnected
	Front passenger's weight sensor (front outer side) 3P connector (on the front passenger's seat wire harness): disconnected
Test point 1	Front passenger's weight sensor (front outer side) 3P connector No. 1 (on the front passenger's seat wire harness)
Test point 2	Body ground

Is there about 5 V or more?


	YES

Short to power in the front passenger's seat wire harness; replace the front passenger's seat wire harness, then clear the DTC.?


	NO

The SWSP3 wire is OK. Short to power in the front passenger's seat wire harness; replace the front passenger's seat wire harness, then clear the DTC.?