Engine Control Module: Diagrams

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Control modules in engine compartment

Engine control module -J623-




Component Location:







Below plenum chamber cover center -Arrow-


121-pin, Pin Arrangements:







A - Engine control module -J623-
121-pin, Pin Connector:

B - 81-pin connector -T81-

C - 40-Pin Connector -T40-

Note::
• The 121-pin connector -T121- is made up of a 81-pin connector -T81- and the 40-pin connector -T40- .




154-pin, Pin Arrangements:







A - Engine control module -J623-
154-pin, Pin Connector:

B - 94-pin connector -T94-

C - 60-Pin Connector -T60-

Note::
• The connector -T154- is made up of a 94-pin connector -T94- and a 60-pin connector -T60- .

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.