Engine Controls - Tests W/codes - 3.1L: Maintenance Oldsmobile Achieva I

CODE 79, TRANSMISSION FLUID OVERTEMP

PCM supplies and monitors a 5-volt reference to sensor. As transmission temperature changes, sensor resistance changes, affecting monitored voltage. When fluid is cold, resistance is high, resulting in a high monitored voltage.When fluid is hot, resistance is low, resulting in a low monitored voltage.

Note. Test numbers refer to numbers on diagnostic chart.

1. Checks to see if code is current or intermittent.