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Home >> Cadillac >> 1990 >> Seville Base, 4T60/ME9 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> ECM Trouble Code Charts >> ECM Code EO37: Shorted Mat Sensor Circuit >> Note On Intermittents
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Note On Intermittents

Manipulate circuit No. 472 wiring, MAT sensor and ECM connector while observing ECM parameter ED05. If failure is induced, manifold air temperature will jump from its normal value to shorted reading of 142-151°C. If wiring and connectors are okay, substitute a known good sensor and retest.

Fig 1: ECM Code EO37 Circuit Diagram
G90F21720
Fig 2: ECM Code EO37 Flow Chart
G90H13711