Mitsubishi OBD / OBD2 Codes >> Montero 3.0L 12V (1994 – 1995)

ModeL Year Engine identification System
Montero 3.0L 12V 1994-95 6G72   MPI

General information

  • Engine control module (ECM) incorporates self-diagnosis function.
  • Malfunction indicator lamp (MIL) will illuminate if certain faults are recorded.
  • ECM operates in backup mode if certain sensors fail, to enable car to be driven to workshop.
  • Trouble codes can be accessed with a voltmeter or a suitable code reader connected to the data link connector (DLC).


  • Ensure ignition switched OFF.
  • Connect an analogue voltmeter between data link 2 4 connector (DLC) 1 [1] [2] terminal 4 or 5 and DLC 2 [1] [1] terminal 25.
  • Switch ignition ON. Do NOT start engine.
  • Voltmeter should be pulsing.
o 1.5 second pulses indicate the ‘tens’ of the trouble code [2] [A].
o 0.5 second pulses indicate the ‘units’ of the trouble code [2] [B].
o A 0.5 second pause separates each pulse [2] [C].
o A 2 second pause separates ‘tens’ and ‘units’ [2] (D].
o A 3 second pause separates each trouble code [2] [E].
o For example: Trouble code 24 displayed [2].
  • If no trouble codes are stored, short pulses will continue to be displayed.
  • If continuous voltage is displayed: Suspect faulty engine control module (ECM).
  • Count voltmeter pulses and compare with trouble code table.
  • Switch ignition OFF.
  • Remove voltmeter.


  • Ensure ignition switched OFF.
  • Disconnect battery ground lead for 15 seconds minimum.
  • Reconnect battery ground lead.
  • Repeat checking procedure to ensure no data remains in ECM fault memory.

NOTE: Disconnecting battery ground lead may erase memory from electronic units such as radio.

Trouble code  identification


Trouble code

Fault location

Probable cause


Heated oxygen sensor (H02S) – front – malfunction

Wiring, H025, fuel system, injectors, ECM


Volume air flow (VAF) sensor- malfunction

Wiring, VAF sensor, ECM


Intake air temperature (IAT) sensor – malfunction

Wiring, IAT sensor, ECM


Throttle position (TP) sensor – malfunction

Wiring, TP sensor, CTP switch, ECM


Engine coolant temperature (ECT) sensor – malfunction

Wiring, ECT sensor, ECM


Crankshaft position (CKP) sensor – malfunction

Wiring, CKP sensor, ECM


Camshaft position (CMP) sensor – malfunction

Wiring, CMP sensor, ECM


Vehicle speed sensor (VSS) – malfunction

Wiring, VSS, ECM


Barometric pressure (BARO) sensor- malfunction

Wiring, BARO sensor, ECM


Ignition timing adjustment

Wiring short to ground


Injectors – malfunction

Wiring, injectors, ECM


Fuel pump – malfunction

Wiring, relay module, fuel pump, ECM


Exhaust gas recirculation (EGR) system – malfunction

Wiring, EGR, EGRT, EGRTVV, hose leak, ECM