DTC B280A-87: No Signal From the Rear Safing Sensor

Special Tools Required

SRS Inflator Simulator 07SAZ-TB4011A

SRS Simulator Lead L 070AZ-SNAA300

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
B280A-87 No signal from the rear safing sensor

DTC (SRS)

1. 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
B280A-87 No signal from the rear safing sensor

Is DTC B280A-87 indicated?

YES

The failure is duplicated. Go to step 2.

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

2. Connector connection check:

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

2. Check the following connector connections.

SRS unit connector B (39P)

Rear safing sensor 2P connector (on the floor wire harness)

Are the connectors OK?

YES

Go to step 4.

Go to step 3.

3. System check:

1. Repair the poor connector connections whichever was the cause of the problem in step 2.

2. Clear the DTCs with the HDS .

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

4. Check for DTCs with the HDS .

DTC Description	DTC
B280A-87 No signal from the rear safing sensor

Is DTC B280A-87 indicated?

YES

Turn the vehicle to the OFF (LOCK) mode, then go to step 4.

The system is OK at this time.

4. Shorted wire check (SSS+ line to SSS- line):

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

2. Disconnect the following connectors.

SRS unit connector B (39P)

Rear safing sensor 2P connector (on the floor wire harness)

3. Measure the resistance between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	SRS unit connector B (39P): disconnected
	Rear safing sensor 2P connector (on the floor wire harness): disconnected
Test point 1	SRS unit connector B (39P) No. 38
Test point 2	SRS unit connector B (39P) No. 39

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

YES

The SSS+ and SSS- wires are not shorted. Go to step 5.

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

5. Shorted wire check (SSS+, SSS- lines):

1. Measure the resistance between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	SRS unit connector B (39P): disconnected
	Rear safing sensor 2P connector (on the floor wire harness): disconnected
Test point 1	SRS unit connector B (39P) No. 38
Test point 2	Body ground

Test point 1	SRS unit connector B (39P) No. 39
Test point 2	Body ground

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

YES

The SSS+ and SSS- wires are not shorted. Go to step 6.

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

6. Shorted wire check (SSS+, SSS- lines to power):

1. Reconnect the negative cable to the 12 volt battery.

2. Turn the vehicle to the ON mode.

3. Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	SRS unit connector B (39P): disconnected
	Rear safing sensor 2P connector (on the floor wire harness): disconnected
Test point 1	SRS unit connector B (39P) No. 38
Test point 2	Body ground

Test point 1	SRS unit connector B (39P) No. 39
Test point 2	Body ground

Is there 0.2 V or less?

YES

The SSS+ and SSS- wires are not shorted to power. Go to step 7.

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

7. Open wire check (SSS+, SSS- lines):

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

2. Connect the black terminal (A) of SRS simulator lead L to the SRS inflator simulator (jumper connector), then connect SRS simulator lead L to the rear safing sensor 2P connector (B) on the floor wire harness.

Courtesy of HONDA, U.S.A., INC.

3. Measure the resistance between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	SRS unit connector B (39P): disconnected
	Rear safing sensor 2P connector (on the floor wire harness): disconnected
	Rear safing sensor 2P connector (on the floor wire harness): connected to SRS simulator lead L
Test point 1	SRS unit connector B (39P) No. 38
Test point 2	SRS unit connector B (39P) No. 39

Is there 1.0 Ω or less?

YES

The SSS+ and SSS- wires are OK. Replace the rear safing sensor , then clear the DTC, and retest. If the DTC is still present, replace the SRS unit .

Open in the floor wire harness; replace the floor wire harness, then clear the DTC.