Note On Intermittents

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

Fig 1: PCM Code E38 Schematic - Open MAT Sensor Circuit

Courtesy of GENERAL MOTORS CORP.

Fig 2: PCM Code E38 Flow Chart - Open MAT Sensor Circuit

Courtesy of GENERAL MOTORS CORP.