DTC P0322 IC Module 4X Reference CKT No Frequency. Oldsmobile Aurora 1997

GM Service Manual Online

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1997 🢒 Aurora 🢒 DTC 🢒 DTC P0322 IC Module 4X Reference CKT No Frequency

Engine Controls Components
Ignition Control (IC) Module
OBD II Symbol Description Notice
ESD Notice
ESD Notice

Circuit Description

The PCM checks for CAM pulses being received without 4X reference pulses.

Conditions for Setting the DTC

Test Conditions

•	DTCs P0340 and P1376 not set.

•	A CAM sensor signal has been received in the last 4 seconds.

Failure Condition

No 4X reference pulses received for 4 seconds.

Action Taken When the DTC Sets

•	PCM uses 24X signal for ignition and fuel control.

•	The Malfunction Indicator Lamp (MIL) will not illuminate.

•	The PCM will command a message to be displayed.

•	The PCM may record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records.

Conditions for Clearing the Message/DTC

•	The PCM will turn the message OFF after one run and pass of the diagnostic test.

•	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. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation.

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.

Check to see if DTC P1376 is set because a REF LO problem can cause other ignition problems.

If DTC P0322 is current, the condition still exists and can be diagnosed directly. If DTC P0322 is history, look at snapshot data to determine conditions under which DTC was set.

Check for proper output of the Electronic Ignition System. If the voltmeter reads 4.1 volts or greater, the Ignition Control Module is able to produce 4X reference pulses.

Checking for 4X reference pulses on Fuel Control circuit from the Ignition Control Module to the PCM. If the frequency is between 30 and 100 Hertz, the PCM is receiving 4X reference pulses.

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.

Checking to see if the DTC P0322 was set while the vehicle was running or not, if MAP value is 80 kPa or less vehicle was running at DTC set. Stray CAM pulses at key ON engine not running can cause DTC P0322 to set falsely.

Step

Action

Value(s)

Yes

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

Go to Step 2

Go to A Powertrain On Board Diagnostic (OBD) System Check

Is DTC P1376 set also?

Go to DTC P1376 Ignition Ground Circuit

Go to Step 3

Start and idle engine.
Select Fail This Ign..

Is DTC P0322 current?

Go to Step 4

Go to Step 9

Record fluid life indexes, turn the key to OFF and wait 30 seconds.
Disconnect PCM connector C2.
Disconnect Ignition Control module connector C4.
Using DMM J 39200 measure the resistance to ground at IC module connector terminal C (harness side).

Is the resistance the same or more than the value specified?

10K ohms

Go to Step 5

Go to Step 12

Measure the resistance between PCM connector C2 terminal 44 and IC module connector C4 terminal C.

Is the resistance the same or less than the value specified?

5 ohms

Go to Step 6

Go to Step 13

Turn the key ON.
Measure the voltage to ground at IC module connector C4 terminal C.

Is the voltage the same or less than the value specified?

0.5 volts

Go to Step 7

Go to Step 14

Reconnect IC module connector C4.
Measure the voltage to ground at PCM connector C2 terminal 44.

Is the voltage the same or more than the value specified?

4.1 volts

Go to Step 8

Go to Step 15

Turn the key to OFF.
Reconnect PCM connector C2.
Install diagnostic jumper at IC module connector C4.

OR:

•	Jumper C4 terminal A to module pin A.

•	Jumper C4 terminal B to module pin B.

•	Jumper C4 terminal C to module pin C.

•	Jumper C4 terminal D to module pin D.

•	Jumper C4 terminal E to module pin E.

•	Jumper C4 terminal F to module pin F.

Set the DMM to 400 mV A/C scale and push the Hz button.
Connect the DMM between jumper C and ground.
Start the engine and measure the FREQUENCY on jumper C.

Is the frequency measured between the range specified?

30 to 100 Hertz

Go to Step 16

Go to Step 15

Check the Failure Rec. for DTC P0322 and check the MAP sensor value when the DTC was set.

Was the MAP sensor value greater than the value specified?

80 kPa

Go to Step 10

Go to Step 11

Check for intermittent short to voltage or EMI (electromagnetic interference) on cam sensor wires.
Check for the following possible causes:

•	Intermittent open or shorted circuit.

•	Wiring run along side spark plug wires.

•	High power transmitters (like mobile radios) operating in the vicinity.

•	A battery charger may also set the DTC.

Was a possible cause located and corrected?