BovineZro

iTrader: (11)

For the sake of context:
Swapped motor and trans (700R4 to T5 swap), trans wiring finished
Steering column swap
91 Camaro Z28, column from 90 Camaro RS

Since I swapped the steering column, I decided to just bypass VATS instead of ordering a new key with the correct chip (the lock cylinder in the replacement column has a different resistance value). Measured resistance on my old key+column (at the connector between the column and body wiring) and came up with 1.142 ohms. This should be the value the Keypass module in the car is expecting. Assumed a correct value of 1.130 ohms based on this document (last page): https://www.lockmasters.com/ecommerc...%20Article.pdf

Created my own resistor pairing @ 1170 ohms (figured this was close enough), car failed to start (SECURITY light on dash). Fair enough. Ordered GM bypass kit (all 15 resistors), disconnect battery, install resistor, wait 10 minutes, reconnect battery, attempt to start - nothing (SECURITY light). Tried next highest (1.470 ohm) and lowest (.887 ohm) in case my original read was bad, disconnecting the battery for at least ten minutes between tries - same thing. I did check the kit's resistors with a multimeter.

Checked resistance on the Passkey wiring connector with each resistor installed to make sure the Passkey module could "see" the resistor; values matched within ~1% (so the issue is not wiring or a loose resistor). Tried two different ECMs on the off chance something was wrong there - one 91 TPI auto and one 91 TPI manual (disconnected battery, swapped ECMs, waited ten mins, reconnected battery).

I'm looking into ordering a key cut to fit the lock cylinder with the correct resistor for the installed Passkey module, but I'm pretty certain that's not going to fix the problem.

Figure the problem is one of the following:

1. Passkey module dead
2. Both ECMs dead (one was working before I started pulling the car apart)
3. Something I'm missing (ie, need to leave battery disconnected for 15 minutes instead of 10)

Thoughts? I know Passkey bypass modules exist (simulates the "ok" signal from the Passkey module to the ECM) but that seems a bit expensive. For the cost, I would rather delete VATS provisions from the ECM, but I don't know how to do it myself so a suggestion for a reputable individual/company would be appreciated. Or, if I'm completely missing something feel free to call me an idiot and point me in the right direction.

Let me know if I left something out. Thanks in advance!

I H8 WWD

iTrader: (5)

I would love to program my ECM without VATS. This way I don't have to change anything of the wiring.

My recent issue (happened twice in the past month) is that sometimes it doesn't recognize my key? or the wiring to the body harness is bad? or whatever. I jiggle the wires, the key, even tilt the column to try and get it to work. This last time I pulled the grey clip holding the 2 wires coming from the ignition cylinder to the body harness and that "fixed" it.

Having only 1 car and only the weekend to work on it it's tough having an issue like this bog you down...and the funny part being is that it's for "security".

If anyone knows how to code the ECM to always be okay with the key inserted that would be awesome.

I'm good with computers, but not trying to splice or add resistors and wiring under my dash. Removal is more like it. Plus I plan to do some ECM tuning in the future so, lets start with something simple?

BovineZro

iTrader: (11)

From what I understand, there are basically three ways to get around VATS:

Resistor bypass - this is ideal because it costs about $.10, and you can unplug the resistor and take it with you if security is a concern. This is what I'm trying to do; it's supposedly super easy if you can read a multimeter. The other nice thing about this is that you can always hook VATS back up; just remove the resistor and reconnect the wiring to the steering column.

Passkey Module bypass - swap in a module that simulates the "all clear" signal from the Passkey module (which is responsible for making sure you have the correct key resistance) to the ECM. Pricey, but it's relatively easy to install. I'm sure there's a lot of snake oil bypass modules out there though, so I was hoping for a recommendation for a good one.

ECM bypass - Remove the VATS provision from the ECM (which lets the car run without VATS) and bypass the starter enable relay (which lets the car start with VATS). The problem with this option is I would need to buy cables and learn new software to do this (assuming it will run on my computer), so I'm trying to find someone who could do this (and maybe verify that my ECM is good in the process).

Again, anyone who knows something I don't feel free to chime in!

BovineZro

iTrader: (11)

Well, someone inadvertently answered my question in another thread; looks like Scott Hansen is a known and respected vendor who can get the ECM VATS delete done for $65: http://www.scotthansen.net/

Before I go that route, I did find a Passkey bypass for significantly less than I had anticipated. eBay has this: http://www.ebay.com/itm/like/281813159375 for $23 with rush shipping. Installation looks easy enough; bypass the starter enable relay and wire this in between the Passkey module and ECM (single wire).

I'll post what I find here. Still looking for any feedback; am I moving things in the right direction or completely off base here?

bigal55

iTrader: (1)

Did you try wiring everything back to stock and consider putting your original key cylinder into the "new" column or is that the reason the column was changed? If it worked prior to you changing the column, it should work in the "new" column. HTH!

BovineZro

iTrader: (11)

I threw in the old column (with the old lock cylinder) when I got rid of my donor car. So that's long gone, sadly. But you're right, that logically makes sense and I would have tried it if I could. Right now the only thing different from stock is the connector to read the key value from the lock cylinder is disconnected at the steering column and a resistor installed inline (similar to the image that I "borrowed" below).



That's why I suspect the Passkey module is the root of the problem; I'm measuring the correct resistance at the connector coming in to the Passkey module (the other end of the purple/white wire pair in the picture), but it's failing to send the all clear to the ECM. It shouldn't matter if I'm getting the resistance from the key or a resistor, as long as the Passkey module sees it. Passkey bypass module should be here by the end of the week, so that will be my next step.

Any other thoughts?

BovineZro

iTrader: (11)

For those who might be curious, the Passkey bypass module (and bypassing the starter relay) did the trick. SECURITY light comes on for about two seconds after turning the key to the run position, then turns off. Starter runs and I'm getting injector pulses and spark. Not bad for a $25 bypass module.

Now I just need to figure out my fuel pump woes...

I H8 WWD

iTrader: (5)

Sounds good.

Now to figure out the way to remove it from the ECM.

I just recently got stuck at work for about 30min when it acted up again and wouldn't let me start my car. I have to get this figured out quickly. I'm still unsure if I should get a laptop or try a new tablet and still unsure what extra chips to buy. Either way...$$$, and I don't want to mess with adding or removing wiring. I've done enough of that lol. Anyway hope we can get part two figured out.

BovineZro

iTrader: (11)

I've read in a couple places that Scott Hansen is the guy to talk to about programming your ECM to remove the provision for VATS. At $65 it doesn't seem unreasonable to me. http://www.scotthansen.net/ I want to get the hardware to do ECM programming some day but spending $200+ will have to wait until my car is up and running again.

Of course if you do reprogram the ECM you will still need to bypass the starter relay but that takes about 2 minutes. And if you create a jumper instead of cutting and splicing the wiring you can easily return it to stock later.

I H8 WWD

iTrader: (5)

^Hell yeah man. Sounds good. Looking at $400 for both OBDI & II tuning kits with 2 extra proms mix and match from ALDLCables and Moates. My buddy had the laptop, so I'm buying all the other equipment. I'd say once I get my tuning gear, I'll throw out How-To's left and right for us on here. I LOVE computers and tuning anything, so add my car to that and I'd be more than willing to show some simple how-to's.