A diagnostic fault code will be set and the light will be turned on if the ignition switch was turned on while the air bag was disconnected. The system should reset when the ignition switch is turned off and back on, but the code will stay in memory.
You probably did this already, but be sure all of the connectors are plugged in securely. Look at the two pins on the back of the air bag. If they are bent over, be very careful when you try to straighten them. There is a shorting bar that touches both pins when the plug is removed to prevent a static electric shock from popping the bag. A nine volt battery is strong enough to pop it, so watch that you don't develop static such as by sliding across the seat.
Next, watch the light very closely. When you turn the ignition switch on, the computer will do a system test for seven seconds. At that point, one of three things will happen. If the light goes out, no problems were detected and the system is armed and ready to pop above a certain speed. If the light flickers off for a fraction of a second, then comes right back on, a problem was detected. The system is disarmed. If the light stays on solidly without flickering at all, a fuse is blown. There are two fuses so when one blows, the other circuit supplies the current to run the light.
If no cause is found for the light being on, you might need to visit the dealer to have the code(s) read with their scanner. Some independent shops can do it too, but not all aftermarket scanners will access the air bag computer. If the code related to "Open Initiator" or "Open Squib" is displayed, that refers to the wire going up the column to the clock spring and air bag. They will try to erase the code. If the light stays off, then the scanner is indeed needed to reset the computer.
Tuesday, March 23rd, 2010 AT 12:54 AM