P0340

Diagnostic Chart:

Schematic:

The Electronic Ignition (EI) module supplies a signal to the PCM based on which cylinder has just fired on its compression stroke. Because of the opposite polarity. the simultaneous fire of #1/#4 or #2/#3 cylinders are of opposite polarity as well. Under most conditions (except low MAP), the waste spark cylinder fires before the compression cylinder in sequence. The EI module can determine which cylinder has fired by the polarity sequence along with Ignition Control (IC) inputs. The EI module can base the cam out signal on either 1/4 or 2/3 cylinder events. The cam out signal along with the double pulse of the 7X ref signal synchronizes spark and fuel timing.

DTC PARAMETERS
DTC P0340 will set if there is no change in the "cam signal in" input for more than 15 crankshaft revolutions when the following conditions have been met:
^ MAP is greater than 30 kPa.
^ The engine is running.

IMPORTANT: The cam signal is continuously checked when crankshaft sensor pulses are received by the PCM, except under low MAP conditions.

DIAGNOSTIC AIDS

IMPORTANT: A cam pulse missing may not affect engine operation.