Code 36, OPTI-Spark High Resolution Pulse: Notes

1994 Pontiac Firebird Trans Am GT, 2D CoupeSECTION Notes

Ignition system supplies 2 timing inputs to PCM, a high resolution signal (360 pulses per camshaft revolution) and a low resolution signal (8 pulses per camshaft revolution). PCM can determine if either timing input is not being received by comparing inputs. If PCM detects low resolution pulse without detecting high pulse, Code 36 will set. Reference signal on resolution line toggles between zero and 5 volts as camshaft turns.

NOTE: Test numbers refer to numbers on diagnostic chart.
  1. Code will set if less than 60 high resolution timing pulses occur between each low resolution pulse and failure occurs 5 consecutive times.
  2. This step determines if PCM is sending out a signal to distributor for processing. If this signal is not available or is shorted to ground or voltage, distributor cannot ground it to produce reference pulses.
RENDER: 1.0x

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