Repair Information
Parts Needed
- Ignition Lock Cylinder
- New Key (s)
- Ecklers – $15/ea 1986-96 Ignition Key VATS (Search for 1986-96 Ignition Key VATS) (Note: Ignition Lock will include a key code, you will need to get the correct Key Code for use with your new lock cylinder. You will then need to have your VATS keys cut with the blank key template that is included with your new lock cylinder)
- Key Code information can be found below.
Key Code Information
This is the most common failure of VATS. This can be bypassed via a Security Override System kit costing $25+, or you can save some money and do it yourself. Either way accomplishes the same thing. One is just mass produced in a stand alone package, the other is home made and only takes a few minutes to actually make if you’re familiar with a soldering iron.
Things you will need before starting:
Using your multimeter, measure the resistance in the ignition key’s resistor pellet. Depending on the resistance, you may need to adjust the range on the multimeter to get the correct resistance amount to display fully.
Things you will need before starting:
- Multimeter that can reads resistance
- Original Corvette ignition key
Using your multimeter, measure the resistance in the ignition key’s resistor pellet. Depending on the resistance, you may need to adjust the range on the multimeter to get the correct resistance amount to display fully.
My key happens to measure 523Ohms, making it Key Code #2.
There are 15 different resistances that GM used in their Pass Key system. Displayed below are the system’s different key codes along with their min/max resistance amount allowed. Once you determine the resistance or Key code number, you can purchase a Security Override System for around $25, or read on to make your own for next to nothing.
For quick reference, I have listed one possible combination for each key code as found in the resistor assortment pack that I purchased for my use. You can use any combination you wish, but it must come within 5%+- of the required resistance needed. When choosing resistors values, you may not always be able to get the exact so you are allowed the same 5% tolerance to work with.
After selecting the possible resistors to make up your resistance amount, temporarily connect them all together in a single row (use tape, putty, bend them together, etc; be creative, but not permanent) and measure the resistance between the first and last resistor in the chain to make sure you have the correct acceptable amount to fall within the 5% tolerance allowed.
There are 15 different resistances that GM used in their Pass Key system. Displayed below are the system’s different key codes along with their min/max resistance amount allowed. Once you determine the resistance or Key code number, you can purchase a Security Override System for around $25, or read on to make your own for next to nothing.
For quick reference, I have listed one possible combination for each key code as found in the resistor assortment pack that I purchased for my use. You can use any combination you wish, but it must come within 5%+- of the required resistance needed. When choosing resistors values, you may not always be able to get the exact so you are allowed the same 5% tolerance to work with.
After selecting the possible resistors to make up your resistance amount, temporarily connect them all together in a single row (use tape, putty, bend them together, etc; be creative, but not permanent) and measure the resistance between the first and last resistor in the chain to make sure you have the correct acceptable amount to fall within the 5% tolerance allowed.
Once you have determined what your key’s resistance is, and which combination of resistors you will need to use, you will now need to go out to your car and clip a connector that is needed so you can bring it back inside to solder the resistors to it.
To get to the steering column, remove the driver’s side hush panel. This is the carpeted piece that your knees rest against under the dash. There are two bolts holding it in place that are located deep within two holes in the carpeting of the hush panel.
[Photo Needed]
Once the hush panel is out, look under the dash at the steering column.
The wires you will be clipping run down the right side of the steering column, originating from the lock cylinder. They should be two very thin wires running together, one Yellow and one Brown. You will also see a connector in the middle of the steering column connecting the wires together, one end going to the lock cylinder and the other going up into the dash.
[Photo Needed]
To get to the steering column, remove the driver’s side hush panel. This is the carpeted piece that your knees rest against under the dash. There are two bolts holding it in place that are located deep within two holes in the carpeting of the hush panel.
[Photo Needed]
Once the hush panel is out, look under the dash at the steering column.
The wires you will be clipping run down the right side of the steering column, originating from the lock cylinder. They should be two very thin wires running together, one Yellow and one Brown. You will also see a connector in the middle of the steering column connecting the wires together, one end going to the lock cylinder and the other going up into the dash.
[Photo Needed]
Bypass Method 1
Part needed
NOTE: You MUST have the correct Key Code before ordering one of these modules!
Once you have the part in hand, simply unplug the connector on the steering column wires and plug one of these modules in it’s place.
[Photo Needed]
It should start right up now.
- Security Override System
- Ecklers – $26 1986-96 Security Override System VATS Code xx (search for VATS)
- Mid America #1 – $25 86-89 VATS Bypass Module (search for VATS)
- Mid America #2 – $60 1986-91Vehicle Anti-Theft Bypass Switch (Includes toggle switch) (Search for VATS)
- Ecklers – $26 1986-96 Security Override System VATS Code xx (search for VATS)
NOTE: You MUST have the correct Key Code before ordering one of these modules!
Once you have the part in hand, simply unplug the connector on the steering column wires and plug one of these modules in it’s place.
[Photo Needed]
It should start right up now.
Bypass Method 2
Parts Needed
Clip the wires between the lock cylinder and the connector. Clip them as high up as you can toward the lock cylinder. You want to leave plenty of excess wire sticking out of the connector in the middle. Once you have clipped the wires, unplug the connector. You should have a connector with several inches of wire sticking out of the end.
[Photo Needed]
Back inside where it is nice and cool, you can now take your time and do this slowly and carefully.
Carefully twist each of the resistors together to look like a chain, one following the other in a row. Don’t worry about the excess wire sticking out of each joint, they will be clipped off once soldered together. Wire each resistor one after the other, as close together as you can to make the resistor chain as short as possible.
[Photo Needed]
Solder each of the twisted pieces of wire together and let them cool.
[Photo Needed]
Clip each of the excess wires off of each solder point so you have one smooth line of resistors all soldered together in a chain.
[Photo Needed]
Now take your connector and solder one of the wires to one end of the resistor chain.
Slip a piece of heat shrink tubing over the resistor chain, leaving slack on each end to cover where you solder the wires to the resistor chain.
[Photo Needed]
Now solder the the other wire to the other end of the resistor chain.
Center the heat shrink tube over the resistors and shrink it. Be careful not to melt the resistors or thin wires from the connector.
You should now have a connector with a chain of resistors wired into a loop between the two wires.
[Photo Needed]
Finally, take the connector back out to the car and plug it back in.
[Photo Needed]
Your car should start right up now.
- Resistors to match your need (or 500 Piece 1/4-watt Resistor Assortment 5% tolerance; Radio Shack Part # 271-312; $12))
- solder iron and solder wire
- heat shrink tubing
Clip the wires between the lock cylinder and the connector. Clip them as high up as you can toward the lock cylinder. You want to leave plenty of excess wire sticking out of the connector in the middle. Once you have clipped the wires, unplug the connector. You should have a connector with several inches of wire sticking out of the end.
[Photo Needed]
Back inside where it is nice and cool, you can now take your time and do this slowly and carefully.
Carefully twist each of the resistors together to look like a chain, one following the other in a row. Don’t worry about the excess wire sticking out of each joint, they will be clipped off once soldered together. Wire each resistor one after the other, as close together as you can to make the resistor chain as short as possible.
[Photo Needed]
Solder each of the twisted pieces of wire together and let them cool.
[Photo Needed]
Clip each of the excess wires off of each solder point so you have one smooth line of resistors all soldered together in a chain.
[Photo Needed]
Now take your connector and solder one of the wires to one end of the resistor chain.
Slip a piece of heat shrink tubing over the resistor chain, leaving slack on each end to cover where you solder the wires to the resistor chain.
[Photo Needed]
Now solder the the other wire to the other end of the resistor chain.
Center the heat shrink tube over the resistors and shrink it. Be careful not to melt the resistors or thin wires from the connector.
You should now have a connector with a chain of resistors wired into a loop between the two wires.
[Photo Needed]
Finally, take the connector back out to the car and plug it back in.
[Photo Needed]
Your car should start right up now.