Test 4: Intermittent

TEST 4: INTERMITTENT

TEST 4		INTERMITTENT
STEP	INSPECTION		ACTION
1	PERFORM PCM RESET TO CLEAR FMEM NOTE: Proceed with this step only if a PCM Reset was not done earlier; otherwise, go to step 2. Eliminating FMEM will insure reproduction of any PCM related symptom. Connect NGS Tester to Data Link Connector (DLC). Key ON, Engine OFF (KOEO). NOTE: Be sure freeze frame data has been recorded before resetting the PCM. Complete a PCM reset. See ON-BOARD DIAGNOSTIC TESTS . Is the PCM Reset complete?	Yes	Go to step 2.
1		No	Complete PCM Reset. Go to step 2.
2	SELECT PIDS RELATED TO THE SYMPTOM A list of PIDs is needed for use with the NGS Tester to indicate the area of fault. See PIN VOLTAGE/PID VALUE CHARTS article for a complete PID list. Highlight each PID related to the symptom. Have all PIDs related to the symptom been chosen?	Yes	Go to step 3.
2		No	Repeat step 2.
3	DECISION TO VERIFY SYMPTOM The path to symptom verification is optional, but is recommended for several reasons; some are because: Vehicle is in for repeat repair. No DTC is present. Customer has difficulty describing the symptom. Does symptom need to be verified?	Yes	Go to step 4.
3		No	Go to step 10.
4	COLLECT ANY AVAILABLE DATA TO AID IN SYMPTOM VERIFICATION NOTE: Only MIL codes will trigger freeze frame data. Prepare freeze frame data for use which was recorded earlier from the DIAGNOSTIC INDEX Continuous Memory DTCs should already be recorded from an earlier test. Access any other available data from the customer. Has all data been recorded?	Yes	Go to step 5.
4		No	Gather as much data as possible to aid in isolation of the intermittent fault area. Repeat step 4.
5	RE-CREATE SYMPTOM USING ALL DATA NOTE: Vehicle may require some driving to proceed with this test step. The concern must be verified by re-creating the conditions that originally set the DTC. With the NGS Tester, select and monitor the same PIDs as displayed in freeze frame along with the previous highlighted PIDs from step 2. Using freeze frame data recorded earlier, re-create the conditions described by each freeze frame PID. Pay special attention to ECT, LOAD, RPM and VSS. Also, use any available customer data to aid in producing the correct conditions for re-creating the symptom. When the symptom occurs, press trigger to begin recording. Could symptom be reproduced?	Yes	Go to step 10.
5		No	Go to step 6.
6	RE-CREATE SYMPTOM USING KOEO ROAD TEST PROCEDURE The road test is the last attempt to locate the area of concern before physically disturbing vehicle circuits. NOTE: PIDs for outputs represent commanded values only. Circuit measurements with digital multimeter indicate actual output status. Therefore, in the case of a fault, the PID and circuit reading on the vehicle may not correspond with each other. PIDs for PCM inputs with a mismatch to the circuit measurement indicate a possible PCM concern. NOTE: PIDs selected from the PID/DATA MONITOR table, The Intermittent Road Test Procedure is a set of instructions for monitoring PIDs with the NGS Tester of circuit measurements with a digital multimeter. This is done under four different conditions - KOEO, HOT IDLE 48 and 88 kmh (30 and 55 mph). Use the PID/DATA MONITOR to compare with the actual vehicle values. For 48 and 88 kmh (30 and 55 mph) procedures, a planned route with passenger is required. Locate the corresponding Reference Value Chart. Set vehicle up to measure PCM terminal voltage with a digital multimeter and NGS Tester. Connect NGS Tester to DLC. Key ON, Engine OFF (KOEO). With the NGS Tester, select and monitor PIDs and also measure PCM terminal voltage shown in the Reference Value Chart. NOTE: PIDs selected from the PID/DATA MONITOR table, Compare the NGS Tester PIDs and digital multimeter values to the values listed in See PIN VOLTAGE/PID VALUE CHARTS article . Are any values out of range?	Yes	Go to step 10.
6		No	Go to step 7.
7	RE-CREATE SYMPTOM USING HOT IDLE ROAD TEST PROCEDURE Key ON, Engine Running (KOER) and at least 87°C (195°F). Continue to monitor the same PIDs and PCM terminal voltage as in the previous step at hot idle. Are any values out of range?	Yes	Go to step 10.
7		No	Go to step 8.
8	RE-CREATE SYMPTOM USING 48 KMH (30 MPH) SLOW CRUISE ROAD TEST PROCEDURE Drive vehicle on preplaned route. Continue to monitor the same PIDs and PCM terminal voltage during slow cruise as in the previous step. Are any values out of range?	Yes	Go to step 10.
8		No	Go to step 9.
9	RE-CREATE SYMPTOM USING 88 KMH (55 MPH) HIGH CRUISE ROAD TEST PROCEDURE Continue to drive vehicle on preplaned route. Continue to monitor the same PIDs and PCM terminal voltage during high cruise as in the previous step. Are any values out of range?	Yes	Go to step 10.
9		No	It is now necessary to physically disturb selected vehicle circuits in an attempt to re-create the intermittent concern. Go to step 10.
10	SELECT CIRCUITS FROM THE PID/DATA MONITOR TABLE Remain in the PID selection menu with the NGS Tester. If the Intermittent Road Test was used to verify the symptom, highlight PIDs or signals that displayed a mismatch to PCM terminal voltage. Proceed to See PIN VOLTAGE/PID VALUE CHARTS article . Match selected PIDs to the corresponding circuit in the PID/DATA MONITOR table. There may be more than one circuit to test. If a PID recording was made with the NGS Tester, it may be helpful to replay at this time (Refer to the NGS Tester instruction manual for recorder function). From the PID/DATA MONITOR table, select and proceed to the appropriate test: Input Test - Used on sensing devices such as temperature, position or oxygen. Output Test - Used on output devices such as relays, coils or solenoids. Has a test been chosen?	Yes	For Input Test: Go to step 11. For Output Test: Go to step 15.
10		No	To diagnose other driveability symptoms. See DIAGNOSTIC INDEX .
11	KOEO INPUT TEST PROCEDURE FOR PCM SENSORS WARNING: When performing any of the test steps, always be aware of hands, clothing or tools near cooling fans or hot surfaces. Using circuits chosen from the PID/DATA MONITOR table, select only the recommended PID(s) to monitor with the NGS Tester. If a PID is not available for the circuit, use a digital multimeter. Proceed to the area of the suspect wiring or component fault. Key ON, Engine OFF (KOEO). If the input is a switch-type component, turn on manually. Monitor the PID or digital multimeter values while tapping on component. Monitor while wiggling sensor harness wire from component to PCM. Look for abrupt changes in values. Compare the actual values to the KOEO PID/DATA MONITOR reference table. See PIN VOLTAGE/PID VALUE CHARTS article . Are values fluctuating in and out of range?	Yes	Repair as necessary.
11		No	Go to step 12.
12	KOER INPUT TEST PROCEDURE FOR PCM SENSORS Repeat step 11 under Key ON, Engine Running (KOER). Are any values fluctuating in and out of range?	Yes	Repair as necessary.
12		No	Go to step 13.
13	KOEO WATER SOAK TEST PROCEDURE FOR PCM SENSORS WARNING: When performing any of the test steps, always be aware of hands, clothing or tools near cooling fans or hot surfaces. Key ON, Engine OFF (KOEO). Continue to monitor PIDs or circuits NGS Tester as in step 12. Proceed to the area of the suspect wiring or component fault. If the input is a switch-type component, turn on manually. Monitor the PID or digital multimeter values while lightly spraying a water mist on the component. Monitor while spraying sensor harness wire from component to PCM. Look for abrupt changes in values. Compare the actual values to the KOEO PID/DATA MONITOR reference table. See PIN VOLTAGE/PID VALUE CHARTS article . Are any values fluctuating in and out of range?	Yes	Repair as necessary.
13		No	Go to step 14.
14	KOER WATER SOAK TEST PROCEDURE FOR PCM SENSORS Repeat step 13 under Key ON, Engine Running (KOER). Are values fluctuating in and out of range?	Yes	Repair as necessary.
14		No	Go to step 19.
15	KOEO OUTPUT TEST PROCEDURE FOR PCM ACTUATORS WARNING: When performing any of the test steps, always be aware of hands, clothing or tools near cooling fans or hot surfaces. NOTE: PIDs selected from the PID/DATA MONITOR table, See PIN VOLTAGE/PID VALUE CHARTS article . will display commanded values only. Digital multimeter measurements will display actual values. Using circuits chosen from the PID/DATA MONITOR table. See PIN VOLTAGE/PID VALUE CHARTS article select the recommended PID(s) to monitor using the NGS Tester. Also, use a digital multimeter to compare circuit values with the NGS Tester PID values. If PIDs are not available for a particular circuit, look for a digital multimeter fluctuation to occur when doing any of the following tests. NOTE: Output Test Mode may not control some outputs, such as injectors and ignition coils. To test these output types, go to step 16. Caution must be used for the next steps. Cooling fans or fuel pump may turn on. Key ON, Engine OFF (KOEO). With the NGS Tester turn all outputs on using Output Test Mode See PIN VOLTAGE/PID VALUE CHARTS article . Proceed to the area of the suspect wiring or component fault. Monitor the PID and digital multimeter values while tapping on component. Monitor while wiggling actuator harness wire from component to PCM. Look for abrupt changes or PID to digital multimeter value mismatches. Also, compare the actual values to the KOEO PID/DATA MONITOR reference table. Is there a mismatch or are any values fluctuating in and out of range on the PID/DATA MONITOR REFERENCE table?	Yes	Repair as necessary.
15		No	Go to step 16.
16	KOER OUTPUT TEST PROCEDURE FOR PCM ACTUATORS WARNING: When performing any of the test steps, always he aware of hands, clothing or tools near cooling fans or hot surfaces. Key ON, Engine Running (KOER). Proceed to the area of the suspect wiring or component fault. Monitor PIDs with the NGS Tester (if PIDs are available) using the PID monitor function. Compare the digital multimeter values with NGS Tester or look for a fluctuation in idle while tapping on the component. If a coil has been tapped and is suspect, with key off, it may be helpful to remove the coil and measure continuity from the spark plug terminal to the signal terminal while tapping the coil. A large fluctuation in resistance will indicate an intermittent open. Otherwise, monitor while wiggling actuator harness wire from component to PCM. Look for abrupt changes in idle or PID to digital multimeter value mismatches or fluctuation. Also, compare the actual values to the HOT IDLE PID/DATA MONITOR reference table. See PIN VOLTAGE/PID VALUE CHARTS article . Is there an idle fluctuation, a digital multimeter value mismatch or fluctuation?	Yes	Repair as necessary.
16		No	Go to step 17.
17	KOEO WATER SOAK TEST PROCEDURE FOR PCM ACTUATORS WARNING: When performing any of the test steps, always be aware of hands, clothing or tools near cooling fans or hot surfaces. NOTE: Output Test Mode may not control some outputs, such as injectors. To test these output types, go to step 18. Key ON, Engine OFF (KOEO). With the NGS Tester, turn all outputs on using Output Test Mode. See PIN VOLTAGE/PID VALUE CHARTS article . Proceed to the area of the suspect wiring or component fault. Monitor the PID and digital multimeter value while spraying a light mist of water on the component. Monitor while spraying actuator harness wire from component to PCM. Look for abrupt changes or PID to digital multimeter value mismatches. Also, compare the actual values to the KOEO PID/DATA MONITOR reference table. See PIN VOLTAGE/PID VALUE CHARTS article . Is there a PID to digital multimeter value mismatch or fluctuation in and out of range according to the PID/DATA MONITOR REFERENCE table?	Yes	Repair as necessary.
17		No	Go to step 18.
18	KOER WATER SOAK TEST PROCEDURE FOR PCM ACTUATORS Repeat step 17 under Key ON, Engine Running (KOER). Is there an idle fluctuation, value mismatch or values fluctuating in and out of range according to the PID/DATA MONITOR REFERENCE table?	Yes	Repair as necessary.
18		No	Key OFF. Go to step 19.
19	INSPECT FOR INTERMITTENT MECHANICAL CONCERNS. NOTE: It is possible for an intermittent mechanical concern to cause a good PCM system to react abnormally. An inspection of mechanical systems relating to the DTC or symptom should have been performed earlier. If not, visually inspect at this time. Look for the possibility of wires, vacuum lines or hoses that may short or kink during normal engine operation, such as: Engine rock during acceleration. Components moving during conditions of vibrations (high rpm or rough road). Accelerator or transmission linkage contact or interference. Is a mechanical concern detected?	Yes	Repair as necessary.
19		No	Unable to verify fault.