maxima airbag problem

Question
My airbag light was on.After computerized check according to the result which is - Prog.No. 303F . Self-DIAG (CURRENT)
DTC RESULTS
SIDE MODULE LH (OPEN)(B1134)I have to replace the side module.
I change the module for $500.Two days after the light was on again.After computerized check the result is the almost the same as before except this time the Self-DIAG was (PAST)and the mechanic said that the module was unplugged and fixed it.
I should be grateful if you could explain me the difference
between PRESENT AND PAST SELF DIAG.

Answer

Sometimes the fault codes remain in a "history" file in the control module and unless you clear all the codes, they may come back.  Also, a poor connection the first time could have triggered a second identical code and rebooting the connectors often repairs that.