DTC A2-1x: Faulty Power Supply (VB line)

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.

• 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 .

  Is DTC A2-1x 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.

• 2. Fuse check:

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

  2. Check the following fuse.

  Fuse	No. B3 (10 A)
  Location	Under-dash fuse/relay box

  Is the fuse OK?

  YES 

  Go to step 3.

  NO 

  Replace the fuse, then turn the vehicle to the ON mode. If the fuse blows again, check for a short to ground in the under-dash fuse/relay box No. B3 (10 A) fuse circuit (dashboard wire harness); replace the dashboard wire harness, then clear the DTC, and retest. If the DTC is still present, replace the under-dash fuse/relay box , then clear the DTC.

• 3. Open wire check (VB line):

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

  2. Disconnect the following connector.

  SRS unit connector A (39P)

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

  4. Turn the vehicle to the ON mode.

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

  Test condition	Vehicle ON mode
  	SRS unit connector A (39P): disconnected
  Test point 1	SRS unit connector A (39P) No. 38
  Test point 2	Body ground

  Is there 12 volt battery voltage?

  YES 

  The VB wire is OK. Faulty SRS unit or poor connection at SRS unit connector A (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 dashboard wire harness.

  NO 

  Open in the dashboard wire harness or faulty under-dash fuse/relay box; replace the dashboard wire harness or the under-dash fuse/relay box , then clear the DTC.