No start issues again

[Doubeleive]

please answer the questions i asked to clarify the issue, we can't read your mind

 

[wjburken]

please answer the questions i asked to clarify the issue, we can't read your mind

 

[Doubeleive]

View attachment 367971

Well since no start can mean a lot of things.....
key in dead i.e. dead battery
key in click click click i.e. low battery
key in, no starter response i.e. dead battery/bad starter/bad ignition
key in starter runs but engine wont run -at all i.e. no fuel/no spark/bad timing
key in starter runs, engine starts and dies i.e. fuel cutoff
i'm sure i'm missing some

 

[Phisher]

Yeah but doesn't the OnStar system have to run through the stereo cuz as soon as I started hooking wires back up all of a sudden things on my dashboard started turning off and Gauges started working again..... And as of now it still doesn't start but all security lights have shut off the only thing that lights up on the dashboard now is the service engine light and the gauges work

 

[Phisher]

so from what I gather from a variety of post information is it will not start and security light may or may not be flashing?
so question?
by no start do you mean the starter turns but the engine will not run? (like it has no fuel, so it just spins?)
or is the starter not turning at all?
presuming it is spinning and you have confirmed it has fuel, then next up is spark
have you confirmed it has spark or no?
if it has spark and fuel then you really need some kind of tech tool to confirm it has correct air reading and timing.
check all fuses! every single one.
you mentioned the instrument cluster not showing things correctly? like low fuel, etc? this would lead me possibly to a bad ground, without going deep down that rabbit hole I would check the basic stuff around the battery and engine bay and body grounds under the front end and confirm the grounds are good

The engine just cranks over and over and over I've replaced the fuel pump because I thought that was my issue then still get nothing just crank over instrument panel shows an empty tank even though it's a full tank and even the lighted up low fuel not only the gauge so I pulled the relay and jumped it by putting a wire from pin 30 to pin 87 the fuel pump works but I still get no start I have gas coming out at the engine but it just turns and turns. about a month ago a month and a half I couldn't start the vehicle at all had to have it towed to a shop and $2,000 later I had the passlock system reset and new ignition put in all that good stuff.. now as far as checking spark I've been told that that would have nothing to do with this that I have some sort of short or once again the passlock system or security system is screwing up and locking it out and it's just frustrating because I bought this vehicle the week after Christmas for about 4 grand then dumped another two grand in and now I'm about another thousand into with what I've done to it this week and it still doesn't run at this point I'm considering just taking it to a scrap yard I don't know what else to do but hopefully rockola1971 and I can converse here in the next week and maybe get it figured out cuz that man has been filling me full of knowledge

 

[Phisher]

if it is still blinking after they replaced it then how did you drive it home? presuming they did what they said they did it should not have even started up if the light is blinking, if you are driving around and the light is blinking then they did not replace it and simply bypassed it or did something wrong.

It has blinked since the moment I put the key in the evening I took it home from the shop I just found out today too after calling them once again that the three wires in the ignition one of them was loose and they forgot to put it back in so maybe I should check that and sure enough I opened the neck of the steering column and the yellow wire isn't even in so obviously they bypassed something just to get it running now I'm at a loss but again once I started hooking the stereo back up and it's hard wired not just a harness I lost everything on the dashboard except the check engine light my gauges instead of saying no gas now shows over full so I don't know this is now my second or third vehicle in a row with electrical Gremlins my last was a classic bronco that I parked because the electrical issues that's it for 2 years until I finally sold it next was another Yukon that had major electrical issues and once we figured it out it was the grounds there were so many of them corroded that's the joy of living in Minnesota everything gets eaten away so here we are with another Yukon having the same nightmares I think I'm going back to just owning a bike

 

[Phisher]

Well since no start can mean a lot of things.....
key in dead i.e. dead battery
key in click click click i.e. low battery
key in, no starter response i.e. dead battery/bad starter/bad ignition
key in starter runs but engine wont run -at all i.e. no fuel/no spark/bad timing
key in starter runs, engine starts and dies i.e. fuel cutoff
i'm sure i'm missing some

No start I mean I put the key in I turn the key and it just cranks over and over and over brand new fuel pump brand new fuel filter brand new fuel relay the fuel pump won't work with the relay in but if I jump it with just a wire from pin 30 to pin 87 the fuel pump engages I get fuel at the engine it sprays out of the overflow if I press the release but I still get nothing if I spray starting fluid in I get nothing it wants to turn over but it just will not that is what is my problem

 

[Doubeleive]

The engine just cranks over and over and over I've replaced the fuel pump because I thought that was my issue then still get nothing just crank over instrument panel shows an empty tank even though it's a full tank and even the lighted up low fuel not only the gauge so I pulled the relay and jumped it by putting a wire from pin 30 to pin 87 the fuel pump works but I still get no start I have gas coming out at the engine but it just turns and turns. about a month ago a month and a half I couldn't start the vehicle at all had to have it towed to a shop and $2,000 later I had the passlock system reset and new ignition put in all that good stuff.. now as far as checking spark I've been told that that would have nothing to do with this that I have some sort of short or once again the passlock system or security system is screwing up and locking it out and it's just frustrating because I bought this vehicle the week after Christmas for about 4 grand then dumped another two grand in and now I'm about another thousand into with what I've done to it this week and it still doesn't run at this point I'm considering just taking it to a scrap yard I don't know what else to do but hopefully rockola1971 and I can converse here in the next week and maybe get it figured out cuz that man has been filling me full of knowledge

if it was the security system it "should" start and then die within a second or two
here is some more information on how that works, the gmt 800 should be passlock I

GM PassKey and PassLock overview

Learn how the different versions of GM's Passlock and Passkey immobilizer system work to prevent theft and how to diagnose them

ricksfreeautorepairadvice.com

it could simply be that it needs a crank position relearn

 

[rockola1971]

It has blinked since the moment I put the key in the evening I took it home from the shop I just found out today too after calling them once again that the three wires in the ignition one of them was loose and they forgot to put it back in so maybe I should check that and sure enough I opened the neck of the steering column and the yellow wire isn't even in so obviously they bypassed something just to get it running now I'm at a loss but again once I started hooking the stereo back up and it's hard wired not just a harness I lost everything on the dashboard except the check engine light my gauges instead of saying no gas now shows over full so I don't know this is now my second or third vehicle in a row with electrical Gremlins my last was a classic bronco that I parked because the electrical issues that's it for 2 years until I finally sold it next was another Yukon that had major electrical issues and once we figured it out it was the grounds there were so many of them corroded that's the joy of living in Minnesota everything gets eaten away so here we are with another Yukon having the same nightmares I think I'm going back to just owning a bike

I would disconnect the stereo since it is likely hooked up to something in the dash circuit that it is not suppose to be.

That yellow wire in your column is the Passlock signal wire going from your passlock hall effect switches to your BCM and it MUST BE hooked up for the system to allow the engine to continue to run. As another has said that the passlock system typically allows the vehicle to start up but then immediately shuts it down if the passlock system detects theft or is broken. The passlock system is integrated into the ignition lock cylinder assembly. On earlier models it was a separate module behind the IC. There are 10 possible passlock codes so when a ignition lock is replaced you have a 1 in 10 chance that you wont have to reprogram. Doesnt matter really since reprogramming is stupid easy to do. The tattletale that your vehicle has a broken passlock system or is in security mode active is your passlock light on the IC is blinking continuously.
To program:

Step 1​

Insert your key in the starter, start you car as you usually would and let it stall. Keep the key in the "On" position. In other words, don't turn the key back to the "Off" position. You will know the key is in the "On" position because you can use the A/C, radio and see all the lights on the dashboard when it is in the "On" position.​

Step 2​

Wait until the "Theft Sys" light on your dashboard stays on without blinking. This will take approximately 10 to 15 minutes.​

Start the car immediately once the "Theft Sys" light stays on steadily. Remember to not turn the key off. Your car will now reset the passlock system and start as usual.​

How to Disable a GM Passkey System

Some GM vehicles come with a factory-installed anti-theft system commonly referred to as the passlock or passkey. Due to glitches with these built-in security systems, GM owners may experience problems trying to start their vehicles. When this happens, the security (theft sys) light randomly...

itstillruns.com

 

[Phisher]

I've done this passlock reset several times and it does nothing I can't get the security light to do anything it's either off which I just realized now that there was a blowing fuse for the radio so I replaced that now the light comes back on but it's off once I shut the door so I'm at the point I'm just selling this vehicle I think