LSI Conventional Ignition System

Ignition Signal Circuit:

Code 41 Wiring Diagram:

CIRCUIT DESCRIPTION:

The ECM receives a signal from the ignition system. This signal is a reference to when the ignition coil fires the plugs. The ECM uses this signal to coordinate when to pulse the fuel injector. If the ECM does not receive this signal for 2 seconds, Code 41 will set. The "CHECK ENGINE" light will not be "ON" for this code.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. The ignition system sends an AC voltage that varies while cranking.

2. This will check ECM and the noise suppressor.

3. This tests the noise suppressor.

4. This checks the pickup coil in distributor.

DIAGNOSTIC AIDS:

An intermittent may be caused by a poor connection rubbed through wire insulation or a wire broken inside the insulation. Inspect ECM harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness.