Feasible to create auto-lock from ODBII?
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TECH Enthusiast
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Feasible to create auto-lock from ODBII? I have an LS3 in a '61 Chevy. I would like to be able to have my doors lock at 10mph or something like that.
Anyone know if it's possible to rig something up from the odb port to send a negative signal that I could hook to the door lock? Would be good to send it to the unlock at ign off.
I've been looking to see if there is any aftermarket thing for this but haven't run across anything.
Anyone know if it's possible to rig something up from the odb port to send a negative signal that I could hook to the door lock? Would be good to send it to the unlock at ign off.
I've been looking to see if there is any aftermarket thing for this but haven't run across anything.
Most likely that would have been controlled by the BCM not the ECU but that doesn't mean you can't make something yourself to make it work.
Not that you're going to spend the money to make the switch but an aftermarket ecu would be able to make that possible. I run a Holley system that locks out reverse at speeds above 5mph.
Not that you're going to spend the money to make the switch but an aftermarket ecu would be able to make that possible. I run a Holley system that locks out reverse at speeds above 5mph.
Roger, locking the doors once the car is in motion would come from the body control module not the PCM. Can something be put together using factory or aftermarket parts? Possibly, but at what cost (time and financial). I'm a simple guy so I ask why not just lock the doors if you want them locked?
Since your car is an automatic what would be simpler is setting a switch to activate a relay that locks the doors when you put the car in gear and unlocks them when you move back to park. Some aftermarket alarms will do this.
Since your car is an automatic what would be simpler is setting a switch to activate a relay that locks the doors when you put the car in gear and unlocks them when you move back to park. Some aftermarket alarms will do this.
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I think this would be your best plan of action. Simple but effective.
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Sure it can be done exactly like your describing but it's probably not worth the cost to have someone else design and build something for you for something that just does lock/unlock.
You'd need a micro controller
1 Mcp2551/2515 combo, 2 output resistors and 2 caps
1 linear voltage regulator/I/O caps to feed the micro controller and CAN chips as well as stabilize the voltage.
2 Npn transistor and gate resistor
2 Songle micro relays - These are good for 10 amps
Send the pid request 0x01 0x0D every 100-200ms to get vehicle speed then read the response and convert it to MPH.
A simple program something along the lines of.......
if (speed > 10 && LockPin == LOW) { digitalWrite(LockPin, HIGH);} // turn on lock relay if it's not on and speed is more then 10 mph
else if (speed > 10 && LockPin == HIGH) { digitalWrite(LockPin, LOW);}// if speed is more then 10 mph and lock relay is on turn the relay off
if (speed < 10 && UnlockPin == LOW) { digitalWrite(UnlockPin, HIGH);}// turn on the relay to unlock the doors when speed is less then 10 mph
else if (speed < 10 && UnlockPin == HIGH) { digitalWrite(UnlockPin, LOW);}// IF the unlock relay is on then turn it off
That gives you an idea how simple it is..you could add a timer to the above code to control how long the lock/unlock pulse from the relay lasted if it didn't turn on the relay long enough to activate the locks fully. Hell could even add a delay so that it'd wait X number of seconds before trying to activate the locks again so the locks aren't cycling on and off at parking lot speeds.
If your handy with a soldering iron and spent a couple of hours reading on basic programming for something like an Arduino and a few more hours writing your program and assembling the parts you could build this your self in a couple of nights for about 15 bucks worth of parts on a blank pcb. Hell you could just but an Arduino, a CAN shield and micro relay board for around $30-35 bucks but you'd still need to come up with a regulator to step the voltage down to something a micro controller can worth with and it'd be a bit larger.
You'd need a micro controller
1 Mcp2551/2515 combo, 2 output resistors and 2 caps
1 linear voltage regulator/I/O caps to feed the micro controller and CAN chips as well as stabilize the voltage.
2 Npn transistor and gate resistor
2 Songle micro relays - These are good for 10 amps
Send the pid request 0x01 0x0D every 100-200ms to get vehicle speed then read the response and convert it to MPH.
A simple program something along the lines of.......
if (speed > 10 && LockPin == LOW) { digitalWrite(LockPin, HIGH);} // turn on lock relay if it's not on and speed is more then 10 mph
else if (speed > 10 && LockPin == HIGH) { digitalWrite(LockPin, LOW);}// if speed is more then 10 mph and lock relay is on turn the relay off
if (speed < 10 && UnlockPin == LOW) { digitalWrite(UnlockPin, HIGH);}// turn on the relay to unlock the doors when speed is less then 10 mph
else if (speed < 10 && UnlockPin == HIGH) { digitalWrite(UnlockPin, LOW);}// IF the unlock relay is on then turn it off
That gives you an idea how simple it is..you could add a timer to the above code to control how long the lock/unlock pulse from the relay lasted if it didn't turn on the relay long enough to activate the locks fully. Hell could even add a delay so that it'd wait X number of seconds before trying to activate the locks again so the locks aren't cycling on and off at parking lot speeds.
If your handy with a soldering iron and spent a couple of hours reading on basic programming for something like an Arduino and a few more hours writing your program and assembling the parts you could build this your self in a couple of nights for about 15 bucks worth of parts on a blank pcb. Hell you could just but an Arduino, a CAN shield and micro relay board for around $30-35 bucks but you'd still need to come up with a regulator to step the voltage down to something a micro controller can worth with and it'd be a bit larger.
Sure it can be done exactly like your describing but it's probably not worth the cost to have someone else design and build something for you for something that just does lock/unlock.
You'd need a micro controller
1 Mcp2551/2515 combo, 2 output resistors and 2 caps
1 linear voltage regulator/I/O caps to feed the micro controller and CAN chips as well as stabilize the voltage.
2 Npn transistor and gate resistor
2 Songle micro relays - These are good for 10 amps
Send the pid request 0x01 0x0D every 100-200ms to get vehicle speed then read the response and convert it to MPH.
A simple program something along the lines of.......
if (speed > 10 && LockPin == LOW) { digitalWrite(LockPin, HIGH);} // turn on lock relay if it's not on and speed is more then 10 mph
else if (speed > 10 && LockPin == HIGH) { digitalWrite(LockPin, LOW);}// if speed is more then 10 mph and lock relay is on turn the relay off
if (speed < 10 && UnlockPin == LOW) { digitalWrite(UnlockPin, HIGH);}// turn on the relay to unlock the doors when speed is less then 10 mph
else if (speed < 10 && UnlockPin == HIGH) { digitalWrite(UnlockPin, LOW);}// IF the unlock relay is on then turn it off
That gives you an idea how simple it is..you could add a timer to the above code to control how long the lock/unlock pulse from the relay lasted if it didn't turn on the relay long enough to activate the locks fully. Hell could even add a delay so that it'd wait X number of seconds before trying to activate the locks again so the locks aren't cycling on and off at parking lot speeds.
If your handy with a soldering iron and spent a couple of hours reading on basic programming for something like an Arduino and a few more hours writing your program and assembling the parts you could build this your self in a couple of nights for about 15 bucks worth of parts on a blank pcb. Hell you could just but an Arduino, a CAN shield and micro relay board for around $30-35 bucks but you'd still need to come up with a regulator to step the voltage down to something a micro controller can worth with and it'd be a bit larger.
You'd need a micro controller
1 Mcp2551/2515 combo, 2 output resistors and 2 caps
1 linear voltage regulator/I/O caps to feed the micro controller and CAN chips as well as stabilize the voltage.
2 Npn transistor and gate resistor
2 Songle micro relays - These are good for 10 amps
Send the pid request 0x01 0x0D every 100-200ms to get vehicle speed then read the response and convert it to MPH.
A simple program something along the lines of.......
if (speed > 10 && LockPin == LOW) { digitalWrite(LockPin, HIGH);} // turn on lock relay if it's not on and speed is more then 10 mph
else if (speed > 10 && LockPin == HIGH) { digitalWrite(LockPin, LOW);}// if speed is more then 10 mph and lock relay is on turn the relay off
if (speed < 10 && UnlockPin == LOW) { digitalWrite(UnlockPin, HIGH);}// turn on the relay to unlock the doors when speed is less then 10 mph
else if (speed < 10 && UnlockPin == HIGH) { digitalWrite(UnlockPin, LOW);}// IF the unlock relay is on then turn it off
That gives you an idea how simple it is..you could add a timer to the above code to control how long the lock/unlock pulse from the relay lasted if it didn't turn on the relay long enough to activate the locks fully. Hell could even add a delay so that it'd wait X number of seconds before trying to activate the locks again so the locks aren't cycling on and off at parking lot speeds.
If your handy with a soldering iron and spent a couple of hours reading on basic programming for something like an Arduino and a few more hours writing your program and assembling the parts you could build this your self in a couple of nights for about 15 bucks worth of parts on a blank pcb. Hell you could just but an Arduino, a CAN shield and micro relay board for around $30-35 bucks but you'd still need to come up with a regulator to step the voltage down to something a micro controller can worth with and it'd be a bit larger.
You have 2 options, one is using a BCM, the second is an aftermarket alarm.
Most BCMs can be configured to lock the doors when you put the trans in drive or when it reaches certain speed and unlock them when the shifter is put in park.
Aftermarket alarms can only be programmed to lock when ignition is ON and unlock when switched OFF (at least most common models)
Most BCMs can be configured to lock the doors when you put the trans in drive or when it reaches certain speed and unlock them when the shifter is put in park.
Aftermarket alarms can only be programmed to lock when ignition is ON and unlock when switched OFF (at least most common models)
