Code 36 - OPTI-Spark Ignition System (High Resolution Pulse): Notes

1993 Chevrolet Camaro Z28, Standard, M29SECTION Notes

Ignition system supplies 2 timing inputs to ECM, a high resolution signal (360 pulses per camshaft revolution) and a low resolution signal (8 pulses per camshaft revolution). ECM can determine if either timing input is not being received by comparing inputs. If ECM 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 ECM 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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