Isuzu Trouble Codes OBD1

All Isuzu cars and light truck are equipped with the ODB1 computer system. This system stores trouble codes once the system has malfunctioned. These codes will present themselves as two digit codes and can be read at the check engine light. This system is similar the the GM style of code gathering. To retrieve codes locate the data port connector which is under the dash or the drivers or passengers side or under the hood near the battery or firewall. Once the connector is located use a jumper wire to connect the "A' and "B" terminals. Next, turn the ignition key to the "on" position (do not start the engine). The check engine light will start blinking; the first set of blinks will be the first number of the trouble code. Then a short pause will occur and the second code number will follow. For an example if the check engine light blinks three times and then a short break and then blinks two time the code number will be 32. To restart the code gathering process turn the ignition key to the "off" position and then back "on" again. To clear diagnostic trouble codes once the repair has been made remove the negative battery cable for thirty seconds and reconnect.

Isuzu ODB1 Trouble Code Definitions

Code 12 System normal

Code 13 Oxygen sensor fault

Code 14 Coolant temperature fault

Code 21 TPS signal fault

Code 23 MAT circuit fault

Code 24 Vehicle speed signal sensor fault

Code 32 EGR sensor fault

Code 23 MAP sensor fault

Code 42 Electronic spark timing fault

Code 43 Electronic spark control fault

Code 44 Oxygen sensor fault

Code 51 Prom error

Code 55 ECM fault

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Article first published (Updated 2013-08-16)