Bypass VATs to get it started?
Team Owner
Joined: May 2000
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From: Plantation Florida USAF(Retired) 1966-1990
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I also had this problem like you, and what I did a quick fix was take pencil eraser and rub the pellet end to clean it, and low and below it started. I replaced the key cylinder for proper fix, cause those old ignition cylinder had TSB to replace if this occurs while back.
Thread Starter
Melting Slicks
Joined: Jan 2007
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Go figure: over time someone soldered a resistor between the two yellow VATS wires after the connector, I just discovered. Either the keys are bad or the wrong ones for the VATS and someone was clever enough to put in the correct resistor to make them function. This complicates things, as it's hard to get an accurate measurement of that resistor with my digital VOM. May have to flatbed it to the auto electrician after all.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
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From: Tampa Florida
If someone already put a resistor accross the wires then I doubt this is your problem.....you can ohm across the soldered in resitor/s to make sure they are still good and not broken internally....compare the value you get to the value from your key pellet your having trouble measuring....the values can be off by just a little and still work. You may want to look into a failed "starter enable relay" check the relay's coil for voltage with the key in the on/run position. Coil oltage present indicates that you may just need a new relay. No coil voltage and your back to the VATS module again.
Le Mans Master
Joined: Aug 2000
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From: Australia
Melting Slicks
Joined: Feb 2006
Posts: 2,753
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From: backwoods upstate ny
Tried that. No go.
Go figure: over time someone soldered a resistor between the two yellow VATS wires after the connector, I just discovered. Either the keys are bad or the wrong ones for the VATS and someone was clever enough to put in the correct resistor to make them function. This complicates things, as it's hard to get an accurate measurement of that resistor with my digital VOM. May have to flatbed it to the auto electrician after all.
Go figure: over time someone soldered a resistor between the two yellow VATS wires after the connector, I just discovered. Either the keys are bad or the wrong ones for the VATS and someone was clever enough to put in the correct resistor to make them function. This complicates things, as it's hard to get an accurate measurement of that resistor with my digital VOM. May have to flatbed it to the auto electrician after all.
hook a 12v test bulb to the solenoid "trip" terminal (the small one on the engine side of the starter)...whenever power is sent to the starter that test bulb will glow brightly... maybe even get real fancy and use a 12v LED assy from raddyshack,etc and mount the LED permanently in/below the dashboard (raddyshac p/n 276-011 is under $3 ready for 12v, others for low voltage need a 1k resistor in the circuit)
Last edited by redrose; Jan 4, 2009 at 10:13 AM.
Thread Starter
Melting Slicks
Joined: Jan 2007
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Tried everything, still no go. Hot wired got it to crank but no start. Went on a flatbed to the auto electrician's shop this morning. Thanks for all the suggestions. Learned alot in this exercise.
Pro
Joined: Sep 2001
Posts: 744
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From: Homestead Florida
This happened on my 96 while I was at walmart. I went back into the store and bought a can of brake cleaner and sprayed a tiny shot of it into the ignition (TINY) and then sprayed the key resistor. It started up and I never had another problem come up. Dont forget to wait several minutes before successive attempts to start it.
It worked for me.
good luck
It worked for me.
good luck
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Team Owner
Joined: Mar 2001
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From: Cincinnati, Oh USA
Since your VATS module has a fixed resistor on it already, then you should unplug the clutch safety switch (gear selector sw if auto) and jump the socket. Measure the voltage on the jumper. It should have 12v on it when you hit crank position on the ign sw. If not, then the start enable relay is suspect. The start enable relay closes if the correct value resistance is seen by the VATS module. You can test your starter by jumping 12v to the jumper, your starter should crank because this 12v actuates the starter solenoid on the starter.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
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From: Tampa Florida
Part of VATS also provides low voltage at a specific frequency to the ECM/PCM saying it is OK to fire the injectors. If you bypass the starter enable relay but don't have the VATS signal to ECM/PCM to trigger the injector pulses the car will never run.
Good Luck
Le Mans Master
Joined: Jan 2003
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From: Santa Maria CA
Yes. The Code 46 combined with a no crank condition means just that. The Decoder Module is not giving the ECM the Ok to pulse the fuel injectors for whatever reason. It's going to be the VATS Decoder Module itself, the wiring, or something with the key cylinder.
The Decoder Module is discontinued, and runs about $200 used. If that was not enough, each module is programed with a specific resistance code (1-15). So unless the salvage yard knows the module's resitance that they are selling you, it's a 1 in 15 change that you won't have to figure out a way to find out what code it is, then get new keys made to match.
The Decoder Module is discontinued, and runs about $200 used. If that was not enough, each module is programed with a specific resistance code (1-15). So unless the salvage yard knows the module's resitance that they are selling you, it's a 1 in 15 change that you won't have to figure out a way to find out what code it is, then get new keys made to match.
Le Mans Master
Joined: Aug 2000
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From: Australia
Le Mans Master
Joined: Jul 2007
Posts: 5,043
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From: Tampa Florida
Yes. The Code 46 combined with a no crank condition means just that. The Decoder Module is not giving the ECM the Ok to pulse the fuel injectors for whatever reason. It's going to be the VATS Decoder Module itself, the wiring, or something with the key cylinder.
The Decoder Module is discontinued, and runs about $200 used. If that was not enough, each module is programed with a specific resistance code (1-15). So unless the salvage yard knows the module's resitance that they are selling you, it's a 1 in 15 change that you won't have to figure out a way to find out what code it is, then get new keys made to match.
The Decoder Module is discontinued, and runs about $200 used. If that was not enough, each module is programed with a specific resistance code (1-15). So unless the salvage yard knows the module's resitance that they are selling you, it's a 1 in 15 change that you won't have to figure out a way to find out what code it is, then get new keys made to match.
Nice pics! The "blue" box, just above the radio on the left side of the pic, is also part of the VATS system setup....the "blue" box contains the "cut out" timer and other related refinements.
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I think you'll find that the blue box is the chime module and has nothing to do with VATS.
Le Mans Master
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From: Tampa Florida
Le Mans Master
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From: Santa Maria CA
- 1986 Original Owner -
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From: North Yorkshire, England
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Oh yes, absolutely! The blue box is the chime (Audio Alarm) module and chimes at different rates for SEATBELT, KEY WARNING and LIGHTS ON. It also lights the FASTEN SEATBELT light in the DIC.
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Melting Slicks
Joined: Jan 2007
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The aftermarket battery disconnect switch did it. Heck of a spike there when I connected or disconnected it left a telltale 1 mm puncture on the metal contacts.
The spike affected electronics all over the place, including VATS. We're working thru the systems to find the extent of the damage. Bugger.
The spike affected electronics all over the place, including VATS. We're working thru the systems to find the extent of the damage. Bugger.