NO.20 INTERMITTENT CONCERNS [WL-3]

id0103b5914000

20
Intermittent concerns
DESCRIPTION
•  Symptom occurs randomly and is difficult to diagnose.
POSSIBLE CAUSE
-

Diagnostic procedure

STEP

INSPECTION

ACTION
1
•  Talk to customer.
•  Retrieve vehicle the service history.
•  Does the vehicle have a number of previous repairs and components replaced for a certain symptom?
Yes
Go to appropriate flow chart.
No
Go to the next step.
2
•  Connect the M-MDS to the DLC.
•  If the input is a switch-type component, turn it on manually.
•  Turn the engine switch to the ON position (Engine off).
•  Access the PIDs for a suspect component.
•  Lightly tap on the suspect component, wiggle and pull each wire/connector at the suspect component or PCM.
•  Are any PID values out of range, or do they suddenly change and go back into range?
Yes
Inspect each wire for corrosion, bending or loose terminal crimps.
No
Go to the Symptom Index.
3
•  Start the engine.
•  Lightly tap on the suspect component, wiggle and pull each wire/connector at the suspect component or PCM.
•  Are any PID values out of range, or do they suddenly change and go back into range?
Yes
Inspect each wire for corrosion, bending or loose terminals and poor wire terminal crimps.
No
Go to the next step.
4
•  Accurately spray water on the suspect component wire, component or vacuum line related to the possible malfunctioning area.
•  Are any PID values out of range, or suddenly change and go back into range, or was there a noticeable engine misfire/stumble?
Yes
Malfunctioning occurred while spraying on component:
•  Replace the part and verify the repair.
Malfunctioning occurred while spraying wiring:
•  Inspect each wire for corrosion, bending or loose terminals and poor wire terminal crimps.
Malfunctioning occurred while spraying vacuum line:
•  Repair the vacuum hoses.
No
Inspect the wire and connector at the suspect component for corrosion, bending or loose terminals, poor wire terminal crimps and high tension on the wire.
Repair if necessary.