P1320

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. If the PCM does not receive 4X reference pulses from the Ignition Control Module for more than 0.4 second while the engine is running, DTC P1320 is set.

Conditions for Running the DTC

^ DTCs P0232 and P1376 are not set.
^ Engine speed greater than 568 RPM.

Conditions for Setting the DTC

No 4X reference pulse has been received by the PCM for 0.4 second.

Action Taken When the DTC Sets

^ The Malfunction Indicator Lamp (MIL) will not illuminate.
^ No message will be displayed.

Conditions for Clearing the DTC

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

Diagnostic Aids

^ This DTC may set due to a false start condition in which cranking engine exceeds 568 RPM but does not start.
^ If no fault present check for intermittent opens/shorts in CKT's 430, 539 and 450 or EMI interference on CKT 430.
^ Without 4X reference pulses the vehicle will start although crank time can be extended to as much as 45 seconds. If this DTC is set with a No Start complaint crank the vehicle for 45 seconds before attempting to determine the cause of a No Start condition.

Test Description

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

2. Check to see if other ignition DTCs are set.
3. Checking for power to the ignition control module.
4. Checking if fault is in circuit.
5. Checking if fault is in circuit.
6. Checking if fault is in circuit.
7. IC module output should be 4.2 volts or more.
8. 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 of the male terminals. Ignition Control (IC) module frequency output should be 30 Hz or more.