Jradical

Hi. I'm having a no-crank, no-fuel problem on my camaro.

I previously attempted a VATS bypass using the correct resistor. It didn't work. I took the resistor off and measured the resistance between the purple wire and the white with black stripe. 14.79kOhm!

https://gyazo.com/6e82c0eb7294a461a08dfa51b2a3d825

Shouldn't this be inf since the two wires are separate?

I will restate, this was the purple and black/white wires' resistance being measured with NO resistor in them. The wires of each of them were not connected. I spliced the F-M connector out(that goes to the ignition cylinder for VATS) and got the same reading.

Where should I go to measure it further upstream?

I've never heard of a short that resulted in ~15kohm.

any ideas?

PS: On the Start Enable Relay, the two thick wires are a closed circut as well. 3.7Mohm. Goes to 0 ohm when I forcefully shut the relay. Have not tried jumping the relay. Can I just stick a piece of metal in the contacts?

Thanks.

Jradical

Bypassed the start-enable-relay by pressing contacts together. Engine cranked with absolutely no problem.

Is my best choice one of these?

Would I need the 50hz or the 30hz version?

http://www.bakerelectronix.com/products_vats/

or


Second one is cheaper if it will work.

Would this, for-sure, fix my issue? Is it even VATS? I'm still getting no fuel but I believe that is due to an open in the wiring.

Tuned Performance

iTrader: (92)

This one says in the description 89 up f body.
https://m.ebay.com/itm/GM-VATS-or-PA...ss!90011!US!-1
If you have tbi or a 89 2.8l you can pull the prom and injector pulse should return.
Just a way to check if it’s vats. The engine will run very poorly.

Tuned Performance

iTrader: (92)

Post #35 has the vats wire pin. You can use ecm ground and accessory power pink/blk to power up the device.
https://www.thirdgen.org/forums/elec...pass-vats.html

Jradical

Yet again, I forgot to post my car.

1991 camaro RS 3.1l. You've helped me before in a different thread.

Since it's TPI will this not work?

Tuned Performance

iTrader: (92)

Same ecm the 90-92 1227730 , I don’t believe it will work . I think the ecm needs the cylinder select chip (rfd) redundant fuel device in order for it to fire. No way to do that unless you remove the soldered in prom.

Jradical

Are there any other metheods of testing VATS? I highly doubt it will work considering I am reading a closed circut where it should be open.

Would the bypassers bypass this POS system?

I know the ebay one says up to 89, but it is the same system as the Baker Electronics one, isn't it? 1 wire for 30hz, 1 for 50hz, power and ground. Wanna save myself some $20 bucks here haha.

That being said, I'm not against buying it as a "just in case" VATS is bad. Everything seems to be pointing towards it, but even if it isn't it I'm only out some 20-40.

Any other diagnostics to do before I go ahead and buy one?

Which do you recommend? I believe 1991 camaros used the 30hz for VATS, not the 50, but both modules cover for that.

Tuned Performance

iTrader: (92)

At pin f10 of the ecm a blue wire you would get 2.5-5v if the passkey module is sending the hz signal. I’m not sure of the frequency. I would verify the signal or lack of and take a more permanent solution and have the memcal (computer chip) reprogramed.
The cost would be more for programming. It seems like a simple hz generator so my second opinion would be the eBay device.
It sounds like vats but shorted injectors can cause the injector driver to shut down. You could ohm the injectors or unplug all of them and check for injector pulse. And then there’s the ignition control module. But since you had the no crank that’s kinda leading towards vats but you should verify by testing the voltage at the ecm key on .

Tuned Performance

iTrader: (92)

F10 is in the yellow or green plug of the ecm

Tuned Performance

iTrader: (92)

I wouldn’t put a piece of metal between the contacts. Ground the relay or jumper it. Then see if the engine cranks .

Jradical

I'll test the wire for voltage. Assuming I don't get any, I'm going to go ahead and buy the ebay bypasser.

How would I hook it up? Do you have a diagram for this as well as physical locations?

thanks so much.

EDIT: I already did put the piece of metal there and it cranked fine. I'm assuming that if I use the bypasser I'm going to have to permanently bypass the relay so I will use a jumper as detailed in other VATS bypass posts.

Tuned Performance

iTrader: (92)

https://tpiparts.net/1227730_pinout_diagram
F10 for the vats hz signal
A6 for device power
And ground a12 or d6 &7

Jradical

Oh, I basically just hook it up the way the old vats was.

Are these ports labeled on the ECM?

Thanks you so much. I've never done electrical work before.

Tuned Performance

iTrader: (92)

I’m not sure where the old passkey module is located and where the pinout for the terminals power /ground ect can be found. You would need to cut and splice at the ecm. The ecm terminals are lettered on the back of the ecm connector.

Jradical

Final question, I promise:

A6 seems to be the ECM main power. I take it I splice into the pnk/blk wire and let it run to both the bypasser and the ECM?

would I disconnect the old Pass-key decoder module power going into F10 and just plug directly into the port?

And I also assume for the grounds I would just splice into an existing wire if there is no free ground?

Thanks.

EDIT:

diagram I'm using for colors

http://austinthirdgen.org/mkportal/m...ine_wiring.gif

Tuned Performance

iTrader: (92)

If you would remove the module which I’m not sure where it’s loca at. You would get power on the passkey pink/black wire, ground blk white wire and blue for the ecm signal. I can’t make out the pins in this image.

Tuned Performance

iTrader: (92)

Your correct on everything and can even ground to the metal of the dash if you want.

Tuned Performance

iTrader: (92)

Ecm pin letters and numbers

Tuned Performance

iTrader: (92)

Any updates on all the electrical issues ?

https://www.thirdgen.org/forums/elec...al-issues.html

Jradical

Nope. This post is the update. The only real change is the fact I can get the car to crank by bypassing the start enable relay.

Currently in the process of ripping the dash apart to get ready to replace the VATS module assuming it is faulty.

They really overenineered the dash lmao. bout 2000 screws and I'm 1 step in.

scooter

iTrader: (11)

No, because you would have been measuring resistance in the VATS module, not the wires them selves.


Depending on where you were probing, you would have been measuring resistance across the coil in the starter solenoid.

Pulling the whole dash out, there are about 12 in the dash pad and then only another 8 that hold it onto the car, really they didn't add enough engineering. The rest is all the other stuff you have to remove to get to those screws, but you don't necessarily have to remove all of them.

Jradical

1st answer makes sense. I think the VATS module is bad. Would make sense if there was a short IN the module itself.

Either way I'm probably replacing it. Unless I get the right voltage which would mean that theres an open between VATS and ECM, but I'll think about that when I get to it. I should add though: If I put the resistors on the wire, then measure the resistance across the resistors(2k and 330 in series) it reads 2.03kohm. With the resistors off the wire, I read 2.33kohm on the resistor and 14.7kohm on the wire alone.. Why is their a drop when I measure this? I probed past the female to male connector.

EDIT: This scenario is in the picture I posted in the original post. Same resistor, probe spot was slightly above the connector.

2nd answer makes sense as well. I thought this should be open, but it makes sense if it is a high resistance instead.

It's less the dash that's very hard, more the dash + everything else I need to get to the pass-key module. Shouldn't take more than a few hours MAX tho so it could be worse.

Thanks.

OrangeBird

iTrader: (1)

Here is a picture of just how deep in the VATS module is , it's the small grey box seen hanging right about in the middle of the dash .

I didn't take this apart for the VATS in my case , I had taken it apart because some previous owner had painted the entire interior green , and I was in the process of replacing the entire interior , right down to the carpets , when this shot was taken . The car looks MUCH better now with it's proper grey/black interior

scooter

iTrader: (11)

Again, you can't measure anything with the wires plugged into the VATS. You would have to remove the harness from the VATS THEN measure wires. You're getting resistance from inside the module, which is likely solid state

Jradical

Again, I'm no electrician. Seems I'm mistaken about how this stuff works. Thanks for answering.

VATS delete module arrived today, gonna put it in sometime tomorrow and update this post with what happens.

Tuned Performance

iTrader: (92)

Any update on using the vats bypass module ?

Jradical

Not yet. I decided to replace the fuel pump before I bypassed VATS. I bought a new pump, ripped out the tank, then realized the whole damn assembly is ****ed. Waiting on a whole new fuel sending assembly before bypassing it.

Tuned Performance

iTrader: (92)

If the tank sender was nasty I bet the injectors a gummed up.

Tuned Performance

iTrader: (92)

Any updates ?

Jradical

Sadly not a lot. Got the new fuel sending unit in the tank, got the tank back on and I'm waiting for a new torque wrench to torque the rear suspension back to spec.

I do have one question, though--

When I start the car, I'm just now remembering that the security light comes on for 3-5 seconds, then turns off.

Is there a chance that VATS is good and the start-enable-relay was just bad? Does the security light stay on when it's bad?

I'm planning on testing this by attempting to crank the car with fuel in it before I install the vats bypass. if it starts, great. If it doesn't, I'll test injectors with a NOID light then see what it reads. if no pulse, bypass vats.

Thanks.