CHECK ENGINE request
CHECK ENGINE request |
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If an emission-related fault arises in the automatic transmission, the transmission control module sends a PWM signal at a frequency of 2 Hz from pin 5 to engine control module pin • 61 (Saab Trionic) • 65 (Motronic 4.1) • 39 (Motronic 5.2) The engine control module then causes the CHECK ENGINE lamp (MIL) to light up.
When the ignition key is turned to the ON position, the control module sends a ground pulse for 1 second as a functional check.