Isuzu 2000 Trooper Workshop Manual page 2104

RESTRAINT CONTROL SYSTEM 9J1–3
The SDM displays the trouble codes by flashing the
warning lamp. Each code that is displayed will consist of a
number of flashes which represents the tens digit, a 1.2
second pause, following by a number of flashes which
represents the ones digit of the code. Each code is
displayed one time before moving on to the next code.
After all of the codes have been displayed, the entire code
sequence will continually by repeated until ground is
removed from terminal 4 of the DLC connector.
Two special codes exist when reading in the flash code
mode (Flash Code 12 and Flash Code 13). "Flash Code
12" will always be the first code displayed when the flash
code mode is enable Code 12 is not an indication of a SRS
problem but an indication that the flash code mode has
been enabled. If there are no active or history codes
present, the SDM will display code 12 until ground is
removed from the DLC connector at terminal 4. "flash
Code 13" will be displayed if history codes are present. To
read the history codes a scan tool must be used.