Precautions

- Don't disconnect couplers from ECM (PCM), battery cable from battery, ECM (PCM) ground wire harness from engine or main fuse before confirming diagnostic information (DTC, freeze frame data, etc.) stored in ECM (PCM) memory.
- Diagnostic information stored in ECM (PCM) memory can be cleared as well as checked by using SUZUKI scan tool or OBD-II generic scan tool. Before using scan tool read its Operator's (Instruction) Manual carefully to have good understanding as to what functions are available and how to use it.
- Priorities for diagnosing troubles
If two or more DTCs are stored, proceed to the flow of the DTC which has detected earliest in the order and follow the instruction in that flow.
If no instructions are given, troubleshoot DTCs according to the following priorities.
- DTCs other than fuel trim malfunction (DTC P0171, P0172), EGR (DTC P0400), and misfire (DTC P0300 - P0304).
- Fuel trim malfunction (DTC P0171, P0172) and EGR (DTC P0400).
- Misfire (DTC P0300 - P0304)

- Be sure to read "Precautions for Electrical Circuit Service:" before inspection and observe what is written there.
- ECM (PCM) Replacement or Substitution
When substituting a known-good ECM, check for the following conditions. Neglecting this check may cause damage to known-good ECM.
- Resistance value of all relays, actuators is as specified respectively.
- MAF sensor, manifold absolute pressure sensor, TP sensor and fuel tank pressure sensor are in good condition and none of power circuits of these sensors is shorted to ground.