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Note On Intermittents

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Manipulate circuits No. 472 and 476 wiring, MAT connector, and ECM connector while observing ECM parameter ED05. If failure is induced, MAT will jump from its normal value to open signal circuit reading of -35°C to -40°C. If wiring and connectors are okay, substitute a known good sensor and retest.

Fig 1: ECM Code EO38 Circuit Diagram
G90F21720
Fig 2: ECM Code EO38 Flow Chart
G90I13712