P1323

Circuit Description

The Ignition Control Module creates a 4X signal and a 24X signal that is used by the PCM for ignition and fuel control. In this diagnostic test, the PCM checks for 4X reference pulses being received without 24X reference pulses. When the engine is running and the PCM is receiving 4X reference pulses without 24X reference pulses and the 24X reference signal line is low for 4 seconds, DTC P1323 is set.

Conditions for Running the DTC

^ DTCs P0340 and P1376 are not set.
^ At least 7 CAM edges have been received this engine run cycle.
^ At least one CAM reference pulse was received within the last 4 seconds.
^ Engine speed greater than 496 RPM.

Conditions for Setting the DTC

No 24X reference pulses received by the PCM and the line is low for 4 seconds.

Action Taken When the DTC Sets

^ The PCM will illuminate the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records.

Conditions for Clearing the MIL/DTC

^ The PCM will turn the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.
^ A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.
^ A History DTC will clear after forty consecutive warm-up cycles with no failures of any emission related diagnostic test.
^ Use a scan tool to clear DTCs.
^ Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended.

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

2. Check to see if DTC P1376 is set because a REF LO problem can cause other ignition problems.
5. IC module output should be 4.2 volts or more.
6. A diagnostic jumper can be created with the terminals supplied in the J 38125-A Terminal Repair Kit. Assemble the jumpers and terminals and cover the exposed terminals with heat shrink tubing. Do not cover the spade end of the male terminals.
IC module frequency output should be 200 Hz or more.