Note On INTERMITTENTS
If intermittent code is being set, observe engine performance while manipulating related wiring. Because this code is a no start condition when failure is induced, engine should begin to stall. This will help to isolate location of malfunction.
If crank signal circuit (No. 806) is shorted to voltage at ECM, the ECM will begin checking for distributor pulses and set code "E12" if engine is not turning. As soon as engine starts, the code will become intermittent, but both "SERVICE NOW/SOON" lights will remain on because ECM thinks engine is still cranking.