1996 lumina security light
lumina1996
09-09-2005, 12:31 PM
Can someone help me with the issues below?
I've noticed the security light on a couple of times during short driving trips. Also I have a intermittent no start condition when turning the switch to start. I can't hear a click or any sound . After several tries the lumina starts. The battery is new and test good. No lights dim during the no start period. The cables at the battery and starter are tight and clean.
Is it possible to disable a faulty Pass-key II system on a 1996 3.1L Lumina?"
I've noticed the security light on a couple of times during short driving trips. Also I have a intermittent no start condition when turning the switch to start. I can't hear a click or any sound . After several tries the lumina starts. The battery is new and test good. No lights dim during the no start period. The cables at the battery and starter are tight and clean.
Is it possible to disable a faulty Pass-key II system on a 1996 3.1L Lumina?"
aliazhar
09-09-2005, 01:41 PM
yes its possible to disable Passkey II system...
here is a short note on it...with a circuit diagram and description...
(this is a link to the circuit diagram in JPEG format)
http://files.automotiveforums.com/gallery/showphoto.php?photo=47536
"The PASSkey II signal is a square-wave pulsed-ground. The diagram in my Haynes manual for the 1991 Camaro shows the PASSkey wire going into the ECM, this is the wire you connect the bypass circuit to. If you wish to interface an alarm to it, it's easy to let the alarm's "grounded when armed" wire ground this wire constantly, therefore preventing the ECM from seeing the signal, and keeping the engine from running, even if they have the key, the engine won't start until the alarm is disarmed. Even if they hotwire it it will not start until tha PASSkey signal is applied to the ECM. So anything that grounds out or breaks the path of the signal, or interrupts power to the oscillator will prevent the engine from starting.
*Note. This circuit DOES work. I didn't select the resistance and capacitance values for this circuit. The creator of the circuit claims it produces a 50HZ signal.
This circuit will produce the signal to allow General Motors ECM's with the VATS PASSkey II systems to start fuel delivery. It produces a 50 HZ square wave 50% duty cycle pulsed ground signal. Just get a 555 timer IC and connect it up as follows. A small IC circuit board from RadioShack can hold the 555 and most of the other components.
Parts:
555 timer
16 pin DIP IC PC board
two 0.1 µF ceramic capacitors
1 µF electrolytic capacitor
3.9 K resistor
22 K resistor
100 Ohm resistor
14 Volt Zener diode
Plastic enclosure
Pin 1 is Ground. Pin 8 is + input. Connect a 0.1 µF ceramic cap between these
pins, with short leads, for filtering. Otherwise it may misbehave. Connect pin
8 to 100 Ohm resistor. Connect a 14V Zener diode between pins 1 and 8, banded (+)
end to pin 8, to absorb voltage spikes from starter solenoid or system overvoltage.
Other end of 100 Ohm resistor connects to ECM's "ignition on" signal wire.
Tie pin 4 to pin 8.
Tie pin 6 to pin 2.
Add a 3.9K resistor from pin 7 to pin 8. (A 3.3K will be close enough)
Add a 22K resistor from pin 6 to pin 7. (You could adjust this one for
precision setting, but it's not needed for this application)
Add a 1 µf capacitor (electrolytic OK) + side to pin 6, - side to pin 1.
Add a 0.1µf cap from pin 5 to pin 1.
Output is on pin 3. Connect to VATS wire of ECM. Also connect
alarm to ground this pin to disable fuel delivery when armed.
here is a short note on it...with a circuit diagram and description...
(this is a link to the circuit diagram in JPEG format)
http://files.automotiveforums.com/gallery/showphoto.php?photo=47536
"The PASSkey II signal is a square-wave pulsed-ground. The diagram in my Haynes manual for the 1991 Camaro shows the PASSkey wire going into the ECM, this is the wire you connect the bypass circuit to. If you wish to interface an alarm to it, it's easy to let the alarm's "grounded when armed" wire ground this wire constantly, therefore preventing the ECM from seeing the signal, and keeping the engine from running, even if they have the key, the engine won't start until the alarm is disarmed. Even if they hotwire it it will not start until tha PASSkey signal is applied to the ECM. So anything that grounds out or breaks the path of the signal, or interrupts power to the oscillator will prevent the engine from starting.
*Note. This circuit DOES work. I didn't select the resistance and capacitance values for this circuit. The creator of the circuit claims it produces a 50HZ signal.
This circuit will produce the signal to allow General Motors ECM's with the VATS PASSkey II systems to start fuel delivery. It produces a 50 HZ square wave 50% duty cycle pulsed ground signal. Just get a 555 timer IC and connect it up as follows. A small IC circuit board from RadioShack can hold the 555 and most of the other components.
Parts:
555 timer
16 pin DIP IC PC board
two 0.1 µF ceramic capacitors
1 µF electrolytic capacitor
3.9 K resistor
22 K resistor
100 Ohm resistor
14 Volt Zener diode
Plastic enclosure
Pin 1 is Ground. Pin 8 is + input. Connect a 0.1 µF ceramic cap between these
pins, with short leads, for filtering. Otherwise it may misbehave. Connect pin
8 to 100 Ohm resistor. Connect a 14V Zener diode between pins 1 and 8, banded (+)
end to pin 8, to absorb voltage spikes from starter solenoid or system overvoltage.
Other end of 100 Ohm resistor connects to ECM's "ignition on" signal wire.
Tie pin 4 to pin 8.
Tie pin 6 to pin 2.
Add a 3.9K resistor from pin 7 to pin 8. (A 3.3K will be close enough)
Add a 22K resistor from pin 6 to pin 7. (You could adjust this one for
precision setting, but it's not needed for this application)
Add a 1 µf capacitor (electrolytic OK) + side to pin 6, - side to pin 1.
Add a 0.1µf cap from pin 5 to pin 1.
Output is on pin 3. Connect to VATS wire of ECM. Also connect
alarm to ground this pin to disable fuel delivery when armed.
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