No start no crank

CASSANDRA ROSE

MEMBER
2006 CADILLAC STS
V8
4WD
AUTOMATIC
177,578 MILES

I had my starter replaced a few months ago and everything has been fine. Now yesterday my car wouldnt start. In park I push the button the dash clicks on for a second and shuts off, and nothing else. But if I put the car in nutruel and try to start it all the lights on dash will stay lit and the speed needel goes all the way up then back down like when you actualy start up your car.
But its not even cranking nothing I heard a whine or a hum? But it wont do anything.
My neiborr tried to jump my starter relay but it only created a spark.
i tried to scan it it wont communicat with the engine or something.
i changed relays and fuses charged battery. And the fob battery

and when its in park trying to start normally I get 0 response from the car besides my car lights coming on and the dinging from the door being open.

2006 Cadillac Sts4 push start

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

More than likely this is an issue with the park neutral switch that is part of the transmission.

The way we confirm this is to check the voltage at the switch and make sure there is battery voltage on pin A and then what is coming out of F when in park and neutral.

Here is a guide that will help with this:

https://www.2carpros.com/articles/how-to-check-wiring

The fact that it appears to go through the cluster sweep when in neutral but not park normally means the switch is the issue but I would expect it to start in neutral but there is not only one way that these can fail so we need to test it and see what we are getting.

I am attaching the info below on this and the starter circuit. So, let's start with this and then go from there.

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