2007 Saturn Ion will not crank or start

ehbrown1

Hopefully someone can help with a dilemma. I have a 2007 Saturn Ion, 57,000 miles, was driving it one day and it began to sputter and finally died. Tried to restart, but no luck. After a few minutes, would not even crank over. Battery good, replaced ignition and starter and still will not crank. Checked every fuse and relay in both boxes and everything is good. Tried a battery pack at the underhood post and grounded to block and still nothing. Ignition turns on and dash lights up, relay under dash clicks, security light goes out, but no crank. Frustrating as the car looks and "ran" like new. Cannot locate a detailed schematic.

Michaell

I’m not a mechanic, but did own an ION at one point.

It might be the crankshaft position sensor.

thecardoc3

If it's not cranking, the crankshaft position sensor cannot be the cause. As far as being able to get schematic goes, you can easily get that here____ https://www.alldata.com/diy/en
There are two different starting circuits, plus I don't know if you have an automatic or manual transmission which also affects the circuit. The following is for one of the automatic transmission starting circuits. Note that a scan tool might be required to help in the diagnostics.

The ignition switch is only an input to the body computer, and it outputs power to the under hood fuse block. Fuse 11 is part of that circuit and should only be powered while the key is in the crank position. Fuse 11 provides power to the neutral safety switch which completes the circuit in park or neutral and sends power back to the under hood fuse block PCM control relay for the starter. The PCM will provide a ground command for the relay under the proper conditions and the relay then provides power to the starter solenoid.

All that being said, a failure in that circuit would not cause the car to stop running, it would just prevent you from restarting the car once it was shut off. I have seen cars that won't start with a jump pack while a completely dead battery is in the car. Concentrate all of your testing right now on basic system power. Once you can get this to crank then we can go further if necessary.

ehbrown1

Thank you for the help. Definitely not the crank sensor. Battery is fully charged and used a battery pack under hood to eliminate cable problem theory. Crank relay not receiving signal. Turn key and all lights come on for a few seconds then go out. Frustrating indeed.