Solstice 2006-2008, Sky 2007-2008

Diagnosis & Testing


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.

  1. The following preliminary inspections/tests must be performed:
    1. Ensure that the battery is fully charged.
    3. Ensure that the battery cables are clean and tight.
    5. Inspect for any open fuses.
    7. Ensure that the grounds are clean, tight, and in the correct location.
    9. Inspect for aftermarket devices that could affect the operation of the system.
    11. Search for applicable service bulletins.

  3. Install a scan tool. Verify that the scan tool powers up.
  5. 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.
    Open 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.

  7. 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.
  9. If any of the power mode parameters do not match in any ignition switch position, refer to Power Mode Mismatch.
  11. Ignition ON, view the security indicator. The security indicator should not remain illuminated after the vehicle bulb check has completed.
  13. Attempt to start the engine.
  15. 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.
    Fuel injectors with partially blocked and restricted nozzles, or a malfunctioning solenoid, can cause a no start condition.
    There may be fuel spray at the fuel injectors and the indicated fuel pressure may be correct, yet there may not be enough fuel to start the engine. If the fuel injectors and the injector circuit are OK, and fuel spray is detected, the fuel injector ON time may be inadequate. If the Engine Control Module (ECM) receives incorrect inputs from the various information sensors, the fuel delivered by the fuel injectors may be inadequate to start the engine. Check all the engine data parameters with a scan tool and compare the values indicated with the expected values or the values from a known good vehicle.
    Check the Crankshaft Position (CKP) sensor engine reference signal with a scan tool. Observe the Engine Speed parameter while cranking the engine. The scan tool should indicate a steady 200-300 RPM while cranking. If erratic values, such as sudden spikes in the engine speed are displayed, the engine reference signal is not stable enough for the engine to start and run properly.
    Inspect the engine for good secure electrical grounds.
    If the engine almost starts and then stalls, check for an open in the ground circuits of the CKP sensor and the camshaft position (CMP) sensor.
    Water or foreign material in the fuel can cause a no start or engine will not stay running condition. During freezing weather water can freeze inside the fuel system. The engine may start after 30 minutes in a heated repair shop. The malfunction may not recur until parked overnight in freezing temperatures. Extreme weather conditions can cause contaminated fuel to prevent the vehicle from starting.
    A vehicle that starts and runs after being brought to the repair shop for a no start condition, may have an ignition system that is susceptible to moisture. Spray water on the ignition system components and the wiring in order to check for an engine starting or will not stay running concern