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ON BOARD DIAGNOSTIC (OBD) SYSTEM CHECK
WARNING:
Fire, Shock, and Burn Danger: When performing any diagnostics or service work
use caution. This system has extreme fuel pressures and a high voltage ignition.
CAUTION:
Electronic controls contain static-sensitive parts. Observe the following
precautions to prevent damage to these parts. Discharge body static: before handling the control.
(Make sure power to the control is turned off, contact a grounded surface and maintain contact while,
handling the control). Avoid all plastic, vinyl, and Styrofoam (except antistatic versions) around
printed circuit boards. Do not touch the components or conductors on a printed circuit board with
your hands or with conductive devices.
WARNING: Extreme High Pressure Fuel Rail. The SIDI Fuel Injectors and fuel rail have extremely
high fuel pressures. Do not attempt to remove or service these parts.
This poses a potentially
hazardous situation that if not avoided, could result in severe personal injury or death, damage to
engine and or property.
Verify that none of the following preliminary inspections/tests reveal the cause of the vehicle
concern before beginning diagnosis.
1. Ensure that the battery is fully charged.
2. Ensure that the battery cables are free of corrosion and tight.
3. Inspect for any open (blown) fuses.
4. Ensure that the wire harness grounds are clean, tight, and in the correct location.
5. Inspect the easily accessible systems or the visible system components for obvious
damage or conditions that could cause the concern. This includes checking that all
connections/connectors are fully seated and secured.
6. Inspect for aftermarket devices that could affect the operation of the system.
7. Search for applicable service bulletins.
8. Install a scan tool. Verify that the scan tool powers up.
9. With Ignition ON and Engine OFF, verify communication with all of the control modules on
the vehicle.
10. Verify that Suspect Parameter Number (SPN) 65559 is not set;
11. If SPN 65559 is set, refer to
SPN 65559
.