Can anyone guide me on an issue currently having? 2007 c6 vet is not starting battery is new but when I press the start button it shuts off then after a few seconds it goes to acc mode....

 

I'm confused...how can it "shut off" when it is already off? When you press the start button, it should either start, or nothing happens. What do you mean, "it shuts off"?

 

If you believe the starter button is an issue simply order a new button and see if that fixes your problem, They are not expensive and are still available from GM parts suppliers as I remember.

 

Sold it sorry

 

Here is link, 15 minutes to replace ignition switch go to u-tube to learn.

 

The start button is not like the old days where the starter motor cranked as long as you held the ignition key forward. The start button simply tells the computer to engage the starter motor, which the computer does for a measured period of time. I think it was 5 seconds, tops, but I might be +/- a second or two. Anyway, if the engine does not catch then the starter motor disengages and the car is on On position until you cycle it and try it again.

If the above is what is happening then you have no problem with the start button, your problem is elsewhere. From there, the reasons why it is not starting are many, but a start button is most probably not one of them.

 

Internal Combustion Engines need Fuel, Air and Spark. I would think that if it cranks then you can eliminate start switch and starter motor as bad.
Are plugs getting spark? Is there pressure in the fuel system? Are there any restrictions getting air to the engine? Gotta diagnose.

Starting System Description and Operation
The starter motor(s) on this vehicle are non-repairable. It has pole pieces that are arranged around the armature. Both solenoid windings are energized. The pull-in winding circuit is completed to the ground through the starter motor. The windings work together magnetically to pull and hold in the plunger. The plunger moves the shift lever. This action causes the starter drive assembly to rotate on the armature shaft spline as it engages with the flywheel ring gear on the engine. Moving at the same time, the plunger also closes the solenoid switch contacts in the starter solenoid. Full battery voltage is applied directly to the starter motor and it cranks the engine.

As soon as the solenoid switch contacts close, current stops flowing thorough the pull-in winding because battery voltage is applied to both ends of the windings. The hold-in winding remains energized; its magnetic field is strong enough to hold the plunger, shift lever, starter drive assembly, and solenoid switch contacts in place to continue cranking the engine. When the engine starts, pinion overrun protects the armature from excessive speed until the switch is opened.

When the engine control module (ECM) sees an engine run flag, the ground is removed from the control circuit of the CRANK relay. The switch side of the CRANK relay opens and battery voltage is removed from the starter solenoid S-terminal. Current flows from the motor contacts through both windings to the ground at the end of the hold-in winding. However, the direction of the current flow through the pull-in winding is now opposite the direction of the current flow when the winding was first energized.

The magnetic fields of the pull-in and hold-in windings now oppose one another. This action of the windings, along with the help of the return spring, causes the starter drive assembly to disengage and the solenoid switch contacts to open simultaneously. As soon as the contacts open, the starter circuit is turned off.

Circuit Description
When the ignition mode switch is placed in the START position, a discrete input is sent to the body control module (BCM) notifying it that engine start has been requested. The BCM then verifies that the brake pedal has been depressed with a discrete input from the brake pedal position sensor and that the key fob, with the correct code, is in the vehicle. After this information has been verified the BCM grounds the control side of the RUN/CRANK relay closing the switch side of it and allowing battery positive voltage to flow from the BATT 3 fuse through the RUN/CRANK relay switch, engine control module (ECM) fuse to the battery positive voltage side of the CRANK relay coil. The BCM also sends a high speed GMLAN message to the ECM requesting engine start. The ECM will then verify that the internal mode switch (IMS) is in Park / Neutral or the clutch pedal is fully depressed. After this has been verified the ECM the supplies ground to the control circuit of the CRANK relay closing the CRANK relay switch circuit and allowing battery positive voltage to flow through the STARTER fuse, the CRANK relay switch to the S-terminal of the Starter solenoid cranking the engine. Ground is supplied through the engine block.