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Notes On Intermittents

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 re-test.

Review snapshot data parameters stored with this code to verify failure. If failure is verified, check and repair intermittent wiring connections or sensor.

Fig 1: ECM Code E038, Open Mat Sensor Circuit Schematic
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Fig 2: Flow Chart, Code E038, Open Mat Sensor Circuit
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