Code 21 Air Bag Module (Squib) System

Code No.21, 22 Air bag module (squib) system


These codes are output when the resistance value between the air bag module (squib) terminals in the SDU is out of the normal range. The probable causes of trouble associated with the respective code Nos. are as follows.

Probable cause of trouble

^ Defective clock spring

^ Defective harness, connector

^ Defective air bag module (squib)

^ Defective SDU

Code 21 Probable cause of trouble

^ Air bag module (squib) or harness short-circuited

^ Clock spring short-circuited

Code 22 Probable cause of trouble

^ Air bag module (squib) or harness open-circuited

^ Clock spring open-circuited

^ Connector in loose contact

Diagnostic Chart:

Troubleshooting Chart








Caution

1. After the ignition switch has been placed at the LOCK position and the negative (-) terminal of the battery has been disconnected, wait for more than 60 seconds before starting work. Wind a tape around the disconnected (-) terminal for insulation.

2. Do not attempt to measure the air bag module (squib) circuit resistance. Use of a tester in measuring the circuit resistance will supply current to the squib, or erroneous deployment due to static electricity could cause serious injury.

3. To unlock the SDU connector, put a flat tip screwdriver on the lock spring (metallic portion) of the lock lever as shown, and press it horizontally toward the inside of the unit. In this case, do not force the lock lever up. Do not put the flat tip screwdriver in the clearance between the lock lever and lock spring (metallic portion).