Before Using This Section
Before using this section, you should have performed the On-Board Diagnostic
System Check and determined that:
- The control module and the malfunction indicator lamp (MIL) are
operating correctly.
- There are no Diagnostic Trouble Codes (DTCs) stored, or a DTC
exists but without a MIL.
Several of the following symptom procedures call for a careful visual
and physical check. The visual and physical checks are very important. The
checks can lead to correcting a problem without further checks which may
save valuable time.
Visual and Physical Checks
Check the following items:
| • | The control module grounds for being clean, tight and in their
proper location. |
| • | The vacuum hoses for splits, kinks and proper connections, as
shown on the Vehicle Emission Control Information label. |
| • | The wiring for the following items: |
| • | The following symptom tables contain groups of possible causes
for each symptom. The order of these procedures is not important. If the scan
tool readings do not indicate the problems, then proceed in a logical order,
easiest to check or most likely to cause first. In order to determine if
a specific vehicle is using a particular system or component, refer to Emission Hose Routing Diagram
or
Engine Controls Schematics
for an application. |
Verify the customer complaint.
Locate the correct symptom table. Check the items indicated under that
symptom from the following symptom tables:
