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Note on Intermittents

WARNING: This page is about a different car, the 1990 Cadillac Fleetwood and 1990 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

Manipulate circuits No. 472 and 469 wiring, MAT connector, and ECM connector while observing ECM parameter P.0.5. If failure is induced, MAT will jump from its normal value to open signal circuit reading of -31° to -40°F (-35° to -40°C).

Fig 1: Code E38: Circuit Diagram
G90F17264
Fig 2: Code E38: Flow Chart
G90E14765