Understand and Verify the Customers Concern. The first part of this step is to obtain as much information as possible from the customer. Are there aftermarket accessories on the vehicle- When does the condition occur- Where does the condition occur- How long does the condition last- How often does the condition occur- In order to verify the concern, the technician should be familiar with the normal operation of the system.
The following preliminary inspections/tests must be performed:
- Ensure that the battery is fully charged.
- Ensure that the battery cables are clean and tight.
- Inspect for any open fuses.
- Ensure that the grounds are clean, tight, and in the correct location.
- Inspect for aftermarket devices that could affect the operation of the system.
- Search for applicable service bulletins.
- Install a scan tool. Verify that the scan tool powers up.
Ignition ON, Engine OFF, verify communication with all of the control modules on the vehicle. If the scan tool does not communicate with one or more of the expected control modules, refer to Data Link References.
NOTEOpen the drivers door to ensure Retained Accessory Power mode (RAP) is inactive during this test. The engine may start during this test. Turn the engine OFF as soon as the crank power mode has been observed.
- With a scan tool, access the body control module power mode data display list. Operate the ignition switch through all positions while observing the power mode data parameters. Verify that all the power mode parameters displayed correspond to the ignition key positions.
- If any of the power mode parameters do not match in any ignition switch position, refer to Power Mode Mismatch.
- Ignition ON, view the security indicator. The security indicator should not remain illuminated after the vehicle bulb check has completed.
- Attempt to start the engine.
If the engine does not start and run, inspect for any of the following conditions:
Insufficient fuel can cause a no start condition. Thoroughly inspect the fuel delivery system for sufficient fuel volume to the fuel injectors. Inspect the fuel supply components for partial blockage or restrictions.