[Jsalladin42]

I have a 2007 Cadillac Dts. One day my wife was driving everything working great no problems except for a dead battery the day before and installed brand new battery so everything was working great and she stopped at a stop sign and when she went to pull away the car stalled and has not ran since. Have replaced all relays, fuses, and breakers under hood in fuse block also everything in fuse block under rear seat. Also replaced starter, ecm, underhood fuse block, and also replaced key as well and successfully did the relearn key process as well.Can put the key in switch and turn it to accessories and everything work great. Fuel pump comes on and as all power everywhere. But when you turn key to start position all the gauges go completely right then completely left and dash goes blank for a few seconds then lights back up but engine will not crank or start

Have tried everything I could think of and also have friends and family that are that work on cars and motors for a living and have tried all their advise and suggestions and still no crank no start

 

[Submariner409]

Welcome to the Funny Farm !!!

Your car has its own built-in trouble code system. Do you have a gearhead friend with a handheld diagnostics scanner? The OBD-II code/fault port at the lower edge of the instrument panel, next to the steering column, can be read with the Key: ON to give you any set trouble codes - and there are a couple thousand possibilities. Have you seen a theft warning in the DIC message strip?

Scan the car somehow, use this link to define any found codes, and post it all here. We hope the scanner chosen will report whether each code is Current or History. That narrows the field considerably.

AWH: Cadillac On-Board Diagnostic Trouble Codes (OBD-II)

 

[Jsalladin42]

Already had that does as well and it showed nothing wrong at all except it was not able to read the ecm which was exactly why I replaced the old ecm with brand new programmed ecm and still the same results

And also no theft warning light or notification on dash or during diagnostic test either

 

[Seville sts tell 2050]

It must be a ground

Check ground right in front alternator on passenger fender

 

[Jsalladin42]

Ok so i did exactly what you asked and and made sure that ground is connected correctly. Also thank you so much for your advice, thoughts, and opinion. Any other grounds under hood or anywhere else I should check or any other opinion on what else I can test or check?

 

[Seville sts tell 2050]

Try to start the car while it's in neutral see what will happen also check starter relay fuse swap it with fuse of the same type that's not needed for starting like the ac

 

[Jsalladin42]

Again thank you so much for helping me. Have have done and tried both of those about 2 hours ago but still the same issue. Also bypassed relay altogether, put the key in and turned it to the On position, turned to starter over and had the engine cranking but still no start

 

[Omac]

Check the fuse for the ecm. A blown fuse will prevent the scanner from reading any codes.

 

[Seville sts tell 2050]

Now that we have some cranking spray some starter fluid in throttle body see if it start briefly