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Pcm Code EO23, Est Circuit Problem (2 Of 2)

NOTE: Step numbers refere to test steps of flow chart.
  1. 5)  This checks if HEI module can recognize a voltage on by-pass circuit and stop grounding EST (PCM-controlled timing).
  2. 6)  This checks by-pass signal to module. If by-pass signal is being sent by PCM to HEI, and if module is interpreting by-pass voltage correctly, then module will switch off ground to EST.
  3. 7)  If chart leads to EST CIRCUIT is okay, then a fault may exist in the 6-way connector. Check connector and terminals damage. If connector is okay, plug in connector and retest Code EO23.
Fig 1: PCM Code EO23, Schematic, EST Circuit Problem
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Fig 2: Flow Chart 2 Of 2, PCM Code EO23, EST Circuit Problem
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