9-3 Viggen Coupe (9400) L4-2.3L Turbo (B235) HO (1999)
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Control Module: Description and Operation
Check Engine Request
CHECK ENGINE Request
If an emission related fault occurs in the automatic transmission, the control module will send a PWM signal with a frequency of 2 Hz from pin 5 to
Trionic pin 61. The engine control module then sends a signal to the main instrument unit, which turns on the CHECK ENGINE lamp.
When the ignition key is turned to the ON position, the control module sends a ground pulse for 1 second as a functional check.