jerryz28

I went to start the car today and it wouldn't crank and the security light stays on, I hooked up my reader and got the P1626 code. A few months ago I did the VATS bypass because I was having troubles starting the car and everything was fine until now. I just recently installed LT's, LS6 intake, and a tune by frost. I didn't have the VATS deleted when I got the tune because I already bypassed it. I've done a search but I couldn't find anything with the same problem.

Anyone ever have this happen? I'm stumped right now.

sreve

iTrader: (3)

The best bypass is tuned out it works every time and never
comes back to haunt you.

Ed Wright

iTrader: (1)

Turning VATS off in the PCM won't effect the starter cranking the engine over. Only injector cut off.

sreve

iTrader: (3)

That's not true because it can. It's very common on passlock and passkey
can do this also. VATS failure is seldom text book happens the same way
every time with every car.

Some copy\paste


which allows the engine to be started. If the BCM does not sense the proper resistance at the ignition key, it will not ground the starter enable circuit.

Ed Wright

iTrader: (1)

That has zero to do with the VATS in the PCM, which ONLY controls injector disable. If the starter won't function, shutting VATS off in the PCM won't help. If the starter works, but the engine starts and dies imediately, that part is in the PCM. What you quoted there has nothing to do with the PCM. Only starter function. P1626 is one of the codes you should shut off when disabling VATS.

jerryz28

I went out and tried starting the car again and it fired right up so I took it for a drive and 15min later the security light came on while I was driving. I shut the car off when I got back home, let it sit for a few minutes and started it again and it fired right up. I don't know what to think of it. I just don't want to drive it anywhere and get stranded.

MontecarloDrag

iTrader: (3)

To completely disable the security there are 2 things you need to bypass:

1- The starter relay. If the BCM reads a different resistor than the correct one it will not enable the relay and the engine won't crank. If the key can't be read the BCM will enable the starter relay but it may not send the "fuel enable" signal to the PCM.
To bypass this you need to permanently ground the yellow/black wire. This can't be bypassed with tuning.

2- The fuel enable signal. The BCM reads the resistor's value, if it's wrong the signal won't be sent to the PCM (engine starts and dies).
If the resistor can't be read it MAY send the signal and allow the engine to start, security light will blink.
To bypass this you need to turn off VATS in the tune, the engine will always fire (as long as it cranks).


If you installed a bypass you have either a bad connection or a faulty VATS module (it is integrated into the BCM).
A faulty VATS component will result in erratic behavior and can leave you stranded even if disabled in the tune. The security light will never go off .
Doing the 2 steps described above will allow the engine to always start, but the car can be easily stolen.

Ed Wright

iTrader: (1)

My '98 TA did that at times. The parts guy I deal with at a local GM dealer told me they have had to replace the wire that has a contact plugged into the lock cylinder, and runs down the column and plugs into a harness under the dash. Cured mine.

What mine would do is when it failed to crank over, the security light would stay on after shutting the key back off. Sit there until the light went back off, and it would usually start next try. Maybe not. :-)
Never knee when it would do it. VATS in the PCM had no effect. Knew it wouldn't, but disabled it anyway. That was about five years ago.

Recently, the security light came back on. Never goes off. Starts just fine. I hardly ever drive it anymore. Need to look into it. No codes in any module.
Any ideas?

jerryz28

I'm not the greatest when it comes to electrical stuff on cars. montecarlodrag des the yellow/black wire come off of the BCM? And when you say to permanently ground it out, should I ground it to the body with a screw? If I do that along with my VATS bypass would that fix the erratic starting problem.

I do hear the fuel pump prime when I first turn the key to try to start it. Just thought I'd say that since I didn't state that in my original post.

bare wit me guys, I get really confused when it comes to electrical problems.

jerryz28

I started having this problem again and tried searching before I posted a new thread and I realized this was a thread I started lol. Could anyone help me out with this or answer the question I had in my post before this one?

MontecarloDrag

iTrader: (3)

Yes, that wire comes from the BCM. Pin C11 connector C3 (blue). You can splice it and ground it. If you screw it to the body make sure it is a good metallic ground, no plastic or paint.
The VATS bypass will work good but it may still fail. The best and permanent way is to disable VATS in the tune.