VATs fuse

viewtopic.php?f=36&t=520&p=645&hilit=vats+resistor#p645

viewtopic.php?f=36&t=63&p=3403&hilit=vats+resistor#p3403

http://www.drdetailshop.com/gmpellet.htm

http://www.thirdgen.org/vats_passkey_system

http://www.bulldogsecurity.com/bdnew/ve ... agrams.asp

http://www.bulldogsecurity.com/bdnew/ve ... agrams.asp
BTW before you go nuts chasing what you assume is a VATS related starter issue verify all your fuses and the battery cables are in good condition, I just went thru this with a guy that insisted his vats system was keeping him from starting the car intermittently, it turned out his problem was caused by
(his alternator was marginal, putting out just 13 volts)
and his battery cable ends were corroded

read thru these
 
Thanks grumpy,
Not real clear on one thing thou, will my 89 vette crank over if there is a vats issue? Heres were i'm at. I have new ignition module,cap,rotor and coil. New fuel pump relay, 6 month old fuel pump. Took pump out, 12 volts direct, pumps is strong. When i turn the key, i hear the relay click, and pump run, even ran it manually to the g port 12 volts direct. Car just cranks, pulled plug #3, plug is dry. I dont have a fuel pressure gauge,and my puppy chewed up my scanner and multi-meter, but its obvious the fuel is not getting past the injectors. Filter, regulator and injectors are the only thing i havent checked. But im wondering if the vats or the ECM is not opening the injectors. I also tried to start with the MAF disconnected, before that, there was no codes. I'll try to troubleshoot more this weekend.
 
viewtopic.php?f=32&t=1401

http://members.shaw.ca/corvette86/FuelS ... gnosis.pdf

http://www.joestradingpost.com/vats/

http://vats.likeabigdog.com/

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

viewtopic.php?f=55&t=1241

read thru these threads above and sub linked info carefully
These and most any other vehicle diagram can be found here:

http://www.bulldogsecurity.com/bdnew/tr ... ooting.asp

http://www.bulldogsecurity.com/bdnew/ve ... agrams.asp

C4 Wiring Diagrams
Thought this might be helpful to someone..

MODEL YEAR(S)
CORVETTE 1984 -1985
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System (if Equipped, Ignition Key has Chip) Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 N/A
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK LIGHT BLUE (TYPE A) IN EITHER KICK PANEL
POWER UNLOCK BLACK (TYPE A) IN EITHER KICK PANEL
DOOR TRIGGER WHITE (-) @ UNDER DASH LIGHT
DOMELIGHT SUPERVISION USE DOOR TRIGGER, Requires #775 Relay
TRUNK RELEASE BROWN (-), Requires #775 Relay @ HATCH RELEASE SWITCH
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH WHITE or PURPLE/WHITE @ IGNITION COIL or DISTRIBUTOR
WAIT TO START LIGHT N/A
BRAKE WHITE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM LIGHT GREEN (-) IN DRIVERS KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

MODEL YEAR(S)
CORVETTE 1986 -1989
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System (if Equipped) Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 BROWN (+) IGNITION SWITCH HARNESS
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK LIGHT BLUE (TYPE C) IN EITHER KICK PANEL
POWER UNLOCK BLACK (TYPE C) IN EITHER KICK PANEL
DOOR TRIGGER WHITE (-) @ UNDER DASH LIGHT, See NOTE *3
DOMELIGHT SUPERVISION USE DOOR TRIGGER, Requires #775 Relay
TRUNK RELEASE BLACK (+), Requires #775 Relay @ DECK RELEASE RELAY, See NOTE *2
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH WHITE or PURPLE/WHITE @ IGNITION COIL or DISTRIBUTOR
WAIT TO START LIGHT N/A
BRAKE WHITE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM LIGHT GREEN (-) IN EITHER KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

NOTE *2 the DECK RELEASE Relay is located at the right rear corner of the luggage compartment.

NOTE *3 use the Passenger DOOR LOCK Switch as the MASTER SWITCH when testing.

MODEL YEAR(S)
CORVETTE 1990 -1993
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System (if Equipped, Ignition Key has Chip) Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 N/A
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK LIGHT BLUE (TYPE C) See NOTE *2 IN EITHER KICK PANEL
POWER UNLOCK BLACK (TYPE C) See NOTE *2 IN EITHER KICK PANEL
DOOR TRIGGER BLACK/WHITE (-) and BLACK/YELLOW (-) Use both, See NOTE *3 IN EACH KICK PANEL
DOMELIGHT SUPERVISION WHITE (-), Requires #775 Relay @ UNDER DASH LIGHT
TRUNK RELEASE BROWN (-), Requires #775 Relay @ HATCH RELEASE SWITCH
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH WHITE or PURPLE/WHITE @ IGNITION COIL
WAIT TO START LIGHT N/A
BRAKE WHITE (+) or LIGHT BLUE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM LIGHT GREEN (-) IN EITHER KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

NOTE *2 This is a TYPE "C" DOOR LOCKING SYSTEM, the PASSENGER switch is the MASTER switch for testing.

NOTE *3 The BLACK/WHITE (-) is for the DRIVERS DOOR and the BLACK/YELLOW (-) is for the PASSENGER DOOR, use both and DIODE ISOLATE when connecting to an ALARM SYSTEM.


MODEL YEAR(S)
CORVETTE 1994 -1996
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System, Ignition Key has Chip, Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 N/A
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK RED/BLACK (TYPE C) See NOTE *2 IN EITHER KICK PANEL
POWER UNLOCK ORANGE/BLACK (TYPE C) See NOTE *2 IN EITHER KICK PANEL
DOOR TRIGGER BLACK/WHITE (-) and GRAY/BLACK (-) Use both, See NOTE *3 IN EACH KICK PANEL
DOMELIGHT SUPERVISION BLACK/WHITE (-), Requires #775 Relay IN DRIVERS KICK PANEL
TRUNK RELEASE LIGHT BLUE (-), Requires #775 Relay @ HATCH RELEASE SWITCH
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH RED/BLACK @ ECM, above the BATTERY
WAIT TO START LIGHT N/A
BRAKE WHITE (+) or LIGHT BLUE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM GREEN (-) IN EITHER KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

NOTE *2 This is a TYPE "C" DOOR LOCKING SYSTEM, the PASSENGER switch is the MASTER switch for testing.

NOTE *3 The BLACK/WHITE (-) is for the DRIVERS DOOR and the GREY/BLACK (-) is for the PASSENGER DOOR, use both and DIODE ISOLATE when connecting to an ALARM SYSTEM.
 
Grounds0001.jpg



87vette81big posted this


C4's used a near identical VATS theft deterrent system as other GM cars used in the same Era.
Starter-1.jpg


1st most common problem is a defective ignition key.
Encoded Pellet resistor goes out of calibration or goes Open circuit, reads infinity when checked with a DVM Ohm meter.
1991fuse.png

2nd most common problem is defective VATS ignition lock cylinder.
Broken off thin Litz wires running from lock cylinder to VATS black box module.
Typical problem with 80,000 to 150,000 miles of driving use & engine startups.
Lock cylinder should be replace to cure.
Steering removal is required along with steering lock plate to gain access to remove ignition lock cylinder.

3rd most common problem is bad VATS starter enable relay.
Mounted behind on the center driver information center on my 87 Vette.
May be located elsewhere on your 91 Vette.

4th most common problem is a defective VATS Black box module.

In order of failure rates with No start issues for VATS equipped GM vehicles I have witnessed 1st hand while working in the GM dealerships & small independent repair shops.

If you own MOATES EFI Tuning gear such as the APU1 or OSTRICH EMULATOR 2 as the later I have,
You can bypass the entire C4 VATS system with a simple keystroke from your laptop in 1 second.
Download the BIN or binary file for your car.
Scroll down about 1/2 to 2/3rds of the file page.
Click on enable/ disable VATS option.

Brian
 
Last edited by a moderator:
Heres a collection of vats stuff to help you.

http://vats.likeabigdog.com/

http://www.thirdgen.org/vats_passkey_system

http://www.ecklerscorvette.com/catalogs ... &x=18&y=10

1.VATS measures the resistance of the pellet in your ign key. If it doesn't agree within 5% of the value it will not close the start enable relay and your starter will not crank. It also tells the ECM to not exercise the injectors so the car cannot be push started. The ECM upon determining that the VATS disallowed a crank, will not a crank for 6 minutes.
Most likely your pellet contacts are worn, or the contacts in the ignition switch tumbler are no longer making reliable connection to the pellet. Also, there is a clutch safety switch which forces you to depress the clutch in order for the starter to work (gear selector switch if automatic). The next time you can't crank, jump the clutch safety switch and measure the voltage on the jumper. The voltage should be 12v with the ign sw in crank position. If not, then VATS isn't closing the start enable relay. You can check the ign tumbler contacts by removing the hush panel above the driver's feet and find the two wires from behind the steering column going to a 2 pin connector. Unplug the connector, insert your ign key and measure the resistance across the wires from the steering column. It should measure the same as your pellet. If over 13k ohms, you need a new ign tumbler or key. You can temporarily bypass VATS by clipping a fixed resistor across the 2 wires going into the wiring harness (goes to the VATS module) the same value as your pellet. You can use a 1/4 watt 5% resistor from Radio Shack. Don't permanently bypass VATS because 99% of thefts are done by bashing the column and jumping the ignition.

2.I'm going to wire in a bypass and switch to cure my intermittant VATS problems. Before I go cutting things, I want to make sure I'm working with the right wires.I traced out the wiring to a set of VERY skinny black wires under the steering column which connects to another set of larger black and white wires.Are these the ones I need to be working with?

Yes..the vats wires are very skinny, but there is a pair of them, white in colour, housed in an orange outer. They connect, via a small black plug, to a brown and yellow wire that go directly to the vats module.
The other extremely skinny wires, housed in a black outer, are cruise control wires...! These have a blade-like connector at the end..
IMO you are better off cutting the brown and yellow wires to fit a resistor or by-pass, as they are heavier and easier to work with.
As long as your cont test comes out from the lock column, then it's most likely the correct wires. I think mine were yellow and some other color, i don't recall. Its dark under the dash. It's pretty obvious though. Sitting in the drivers seat, the wires came out of the dash, then ran up right-of-center from the bottom of the steering column up to the lock cylinder.

3. we clipped the wires after the connector (between the lock and the connector) and then I just unhooked the connector and brought it inside.
We then measure the OHMs of the key, and I had bought a large pack of resistors at RadioTrash and we found 3 that gave it the correct OHM reading. We soldered them together and then soldered them to the clipped wires. Now what I had was a connector with 2 wires, and 3 resistors soldered between them which I covered with heat shrink.
I then just went back out to the car, plugged in the connector and the car fired right up with NO problems!! this was after a year of sitting in the driveway scratching my head as to how to make it start... all it took was 3 resistors costing me $.06 total!!the whole project took roughly 15-20 mins to do.

Vats Q and A

VATS can keep your vette from being stolen. 99% of thefts are done by bashing the column and jumping the ignition. The person I bought my 87 from had a 90 and came out of work to broken glass and a bashed column, but the vette hadn't moved an inch. Keep your car in good repair !!!
The VATS module closes the start enable relay and tells the ECM to exercise the injectors by comparing the pellet resistance with the stored number. If the resistance isn't correct, then VATS makes you wait 6 minutes to try again. The starter solenoid gets power through the ign sw crank contact, the start enable relay, and then the clutch safety switch (gear selector switch if automatic). First try your spare ign key as its pellet contacts aren't worn like your everyday key. Next, jump the clutch safety switch and try a crank while measuring the voltage on the jumper. If you don't have 12v on the jumper in crank position, then you will have to determine where the circuit is not continuous. You can test the starter by jumping 12v to the clutch safety switch jumper, the starter should run. Most VATS troubles are due to worn contacts in the ign tumbler that make connection to the pellet. You can check this out by removing the hush panel above the drivers feet and finding the 2 wires from behind the steering column that go to a 2 pin connector. Unplug the connector, insert ign key and measure the resistance across the wires from the column. It should measure the same as the pellet. If over 13k ohms, you need a new ign tumbler which has new contacts that touch the pellet. You can temporarily bypass VATS by connecting a fixed resistor the same value as your pellet across the 2 wires that go into the harness (these go to the VATS module). You can use 1/4 watt 5% resistor from Radio Shack. There is no need to spend $30 for a bypass kit.
Canam is offline Report Post Reply With Quote
 
92ecma.jpg

sec1.jpg

sec2.jpg

Starterbrace.jpg

I just rebuilt both my 1996 and 1985 corvette starters, (totally different designs BTW, THE 1985 PICTURED ABOVE,)
having a remote starter test switch helps isolate the problem, the top pictured switch sells for $38 at napa, the AC-TRON below for about $13 at ADVANCE AUTO

http://www.summitracing.com/parts/ANM-CP7853/
remotestartswitch1.jpg

remotestartswitch2.jpg

these test switches normally cost under $20 and easily test starter function along with a multi meter youll use to test battery voltage etc.
 
Thought this might be helpful to someone..
C4 corvette wire info
MODEL YEAR(S)
CORVETTE 1984 -1985
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System (if Equipped, Ignition Key has Chip) Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 N/A
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK LIGHT BLUE (TYPE A) IN EITHER KICK PANEL
POWER UNLOCK BLACK (TYPE A) IN EITHER KICK PANEL
DOOR TRIGGER WHITE (-) @ UNDER DASH LIGHT
DOMELIGHT SUPERVISION USE DOOR TRIGGER, Requires #775 Relay
TRUNK RELEASE BROWN (-), Requires #775 Relay @ HATCH RELEASE SWITCH
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH WHITE or PURPLE/WHITE @ IGNITION COIL or DISTRIBUTOR
WAIT TO START LIGHT N/A
BRAKE WHITE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM LIGHT GREEN (-) IN DRIVERS KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

MODEL YEAR(S)
CORVETTE 1986 -1989
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System (if Equipped) Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 BROWN (+) IGNITION SWITCH HARNESS
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK LIGHT BLUE (TYPE C) IN EITHER KICK PANEL
POWER UNLOCK BLACK (TYPE C) IN EITHER KICK PANEL
DOOR TRIGGER WHITE (-) @ UNDER DASH LIGHT, See NOTE *3
DOMELIGHT SUPERVISION USE DOOR TRIGGER, Requires #775 Relay
TRUNK RELEASE BLACK (+), Requires #775 Relay @ DECK RELEASE RELAY, See NOTE *2
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH WHITE or PURPLE/WHITE @ IGNITION COIL or DISTRIBUTOR
WAIT TO START LIGHT N/A
BRAKE WHITE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM LIGHT GREEN (-) IN EITHER KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

NOTE *2 the DECK RELEASE Relay is located at the right rear corner of the luggage compartment.

NOTE *3 use the Passenger DOOR LOCK Switch as the MASTER SWITCH when testing.

MODEL YEAR(S)
CORVETTE 1990 -1993
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System (if Equipped, Ignition Key has Chip) Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 N/A
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK LIGHT BLUE (TYPE C) See NOTE *2 IN EITHER KICK PANEL
POWER UNLOCK BLACK (TYPE C) See NOTE *2 IN EITHER KICK PANEL
DOOR TRIGGER BLACK/WHITE (-) and BLACK/YELLOW (-) Use both, See NOTE *3 IN EACH KICK PANEL
DOMELIGHT SUPERVISION WHITE (-), Requires #775 Relay @ UNDER DASH LIGHT
TRUNK RELEASE BROWN (-), Requires #775 Relay @ HATCH RELEASE SWITCH
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH WHITE or PURPLE/WHITE @ IGNITION COIL
WAIT TO START LIGHT N/A
BRAKE WHITE (+) or LIGHT BLUE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM LIGHT GREEN (-) IN EITHER KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

NOTE *2 This is a TYPE "C" DOOR LOCKING SYSTEM, the PASSENGER switch is the MASTER switch for testing.

NOTE *3 The BLACK/WHITE (-) is for the DRIVERS DOOR and the BLACK/YELLOW (-) is for the PASSENGER DOOR, use both and DIODE ISOLATE when connecting to an ALARM SYSTEM.


MODEL YEAR(S)
CORVETTE 1994 -1996
KEY T-HARNESS IMMOBILIZER
N/A N/A GM's VATS ANTI-THEFT System, Ignition Key has Chip, Requires 791 Bypass Module
PART COLOR LOCATION
12 VOLT CONSTANT RED (+) IGNITION SWITCH HARNESS
STARTER YELLOW (+) IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 PINK (+) IGNITION SWITCH HARNESS
IGNITION 2 N/A
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 ORANGE (+) IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 N/A
KEYSENSE N/A
PARKING LIGHTS ( - ) N/A
PARKING LIGHTS ( + ) BROWN (+) @ HEADLIGHT SWITCH
POWER LOCK RED/BLACK (TYPE C) See NOTE *2 IN EITHER KICK PANEL
POWER UNLOCK ORANGE/BLACK (TYPE C) See NOTE *2 IN EITHER KICK PANEL
DOOR TRIGGER BLACK/WHITE (-) and GRAY/BLACK (-) Use both, See NOTE *3 IN EACH KICK PANEL
DOMELIGHT SUPERVISION BLACK/WHITE (-), Requires #775 Relay IN DRIVERS KICK PANEL
TRUNK RELEASE LIGHT BLUE (-), Requires #775 Relay @ HATCH RELEASE SWITCH
SLIDING POWER DOOR N/A
HORN BLACK (-) @ STEERING COLUMN HARNESS
TACH RED/BLACK @ ECM, above the BATTERY
WAIT TO START LIGHT N/A
BRAKE WHITE (+) or LIGHT BLUE (+) @ SWITCH ABOVE BRAKE PEDAL
FACTORY ALARM DISARM GREEN (-) IN EITHER KICK PANEL
ANTI-THEFT See NOTE *1 GM's VATS System @ Ignition Switch

EXTRA INFORMATION

NOTE *1 The VATS (Vehicle Anti-Theft System) wire may be (2) thin YELLOW wires, (2) thin TAN wires or (2) thin WHITE wires, these wires are usually in a ORANGE or BLACK HEAT SHRINK TUBE, but at times are left out of the tube and ran by themselves up under the dash to the Security Module under the Dash.

NOTE *2 This is a TYPE "C" DOOR LOCKING SYSTEM, the PASSENGER switch is the MASTER switch for testing.

NOTE *3 The BLACK/WHITE (-) is for the DRIVERS DOOR and the GREY/BLACK (-) is for the PASSENGER DOOR, use both and DIODE ISOLATE when connecting to an ALARM SYSTEM.

These and most any other vehicle diagram can be found here: http://www.bulldogsecurity.com/bdnew/ve ... agrams.asp
you can,t always trust scanners suggestions either, I recently had a code scanner suggest a cooling fan relay was defective,
replacing it with a known good relay that was working in an identical car had no effect neither relay tested bad either..
the problem was tracked down to a loose ground and a heat sensor that tested good at its rated ohms resistance, but failed to trigger the relay
experience suggested I test the relay by inserting a resistor of the known rated ohms to trigger the relay into the pigtail that connected to the sensor,
a simple test like that proved the sensor was defective as the fan and relay function with the resistor in the pigtail.

pinkl.png

pinkl1.png


https://www.sparkfun.com/products/10969

https://www.jameco.com/z/GB115-1-8-1-4-and-1-2-Watt-Resistor-Grab-Bag-Tolerances-2-5-10-_134130.html


ResistorColorCode.gif



resistor-value-chart-inspirational-4-band-and-5-band-resistor-color-codes-of-resistor-value-chart.jpg


5BandResistor.gif

med_1567548327-Resistor_Pack_for_GM_VAT_By-pass.jpg

https://www.diyaudioandvideo.com/Electronics/ResistorColorCodes/

http://garage.grumpysperformance.co...t-find-whats-wrong-start-with-the-basics.609/
 
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