Note On Intermittents

This code can be caused by an open, short to ground or short to voltage on circuit No. 472 and/or 469. Also check for open or short in sensor connector, engine-to-dash connector or PCM connector. If no problems are found in wiring and connectors, substitute a known good sensor, and retest.

Fig 1: PCM Code E74, Schematic, MAT Sensor Signal Interrupt

Courtesy of GENERAL MOTORS CORP.