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STS not starting. Did everything possible. Its driving me crazy.

4K views 16 replies 10 participants last post by  Ludacrisvp 
#1 ·
I have a 2005 STS V6. When you try to start the car, everything cuts off and nothing happens. about a min later, everything turns back on, including gauges, and just sits there. I have changed the battery, the starter, the relays, the starter switch. alternator is good. i have no clue what to do next?

could it be the Neutral safety switch. when i press the brake before starting it, i hear the NSS click. i have shifted car into neutral to try to start it, it wont work. sometimes if i take off one of the battery terminals, it seems like it resets the car and car will start. i have never had it do this to me in the afternoon, only cold starts in the morning.

i feel like there is a short somewhere causing this. any help would be much appreciated. thank you.
 
#5 ·
Re: Sts not starting. Did everything possible. Its driving me crazy.

Is the SES light on? Have you had the codes scanned?
no ses light on.
Check all the fuses? Is the security light on?

Sounds like my rcdlr when I swapped it to one with the secure car feature. I figured I'd try starting it but no luck. Did exactly what you describe. Had to perform the 30 min security relearn then erase and program the fobs.
no security light on, and all the fuses are good.

its weird, once u try to turn it on, the message display turns off and it shows nothing.
 
#4 ·
Check all the fuses? Is the security light on?

Sounds like my rcdlr when I swapped it to one with the secure car feature. I figured I'd try starting it but no luck. Did exactly what you describe. Had to perform the 30 min security relearn then erase and program the fobs.
 
#8 ·
Re: Sts not starting. Did everything possible. Its driving me crazy.

It sounds to me like a data bus communication problem. You need to scan for codes with a scanner sophisticated enough to scan all the codes and not just ECM.
Ok I will try to get it scanned at Firestone or dealership and see if anything comes up.
I had an old Eldorado that used to do this exact same thing, ended up being bad grounds. They were all somewhat corroded, dirty, loose, etc. After cleaning and tightening the problem went away.
Not saying that it is your problem but something to keep in mind.
I was thinking that also. Car was in a bad front end collision and has a rebuilt title. does anyone know where the ground points are on this car?
 
#7 ·
Re: Sts not starting. Did everything possible. Its driving me crazy.

I had an old Eldorado that used to do this exact same thing, ended up being bad grounds. They were all somewhat corroded, dirty, loose, etc. After cleaning and tightening the problem went away.
Not saying that it is your problem but something to keep in mind.
 
#13 ·
Re: Sts not starting. Did everything possible. Its driving me crazy.

Does anyone know where the ground points are?
Here are a couple pictures that show where they are on an '11 STS (but you can follow the negative (ground) cable and they should lead to the grounding points.

First photo is chassis ground, second photo is engine ground (check for clean and tightness; easy/peasy).



 
#14 ·
Re: Sts not starting. Did everything possible. Its driving me crazy.

Very helpful C&C. thanks alot.

I took off chasis ground and sanded down around it and cleaned off bolt since it had some dirt on it. did this on saturday and car has been starting up.

but just in case, where exactly is the engine ground? driver or passenger side? and is near the motor mounts?
 
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