Automatic door-lock/unlock
CX-9 /2007 Version 1.0
Page 4
Now the charged capacitor C2 will be discharged and relay-B will activate. Contact-B is closed and a
door-lock signal is sent to the contact-D. Contact-D is in NC and the ground signal is sent through a 1K
resistor to the car computer. This indicates a lock signal and the doors will lock. After ~1.5 seconds the
capacitor C2 will have been discharged, relay-B is dropping off and contact-B is returning to NC, stopping
the door-lock signal.
During driving NONE of the relays is activated:
Relay-A is only activated when the parking brake is pressed (on)
Relay-B is only activated for 1.5 seconds to give a pulse (C2 is discharged)
Relay-C was activated for 3 seconds for power-up (C1 is charged)
1D:
When parking brake is pressed again (e.g. on), the parking brake-switch will connect to ground
again. It will activate relay-A with a little delay. Contact-C will activate relay-B by connecting to +12V.
Contact-B is closed and a door-lock signal is sent to the contact-D. Contact-D is in NO and the ground
signal is sent directly to the car computer. This indicates an unlock signal and the doors will unlock.
After ~1.5 seconds the capacitor C2 will have been charged, relay-B is dropping off and Contact-B is
returning to NC, stopping the door-lock signal.
During standstill / parking brake is ON / contact ON only Relay-A is activated:
Relay-A is activated as the parking brake is pressed (ON)
Relay-B is only activated for 1.5 seconds to give a pulse (C2 is charged)
Relay-C was activated for 3 seconds for power-up (C1 is charged)
1E:
if the parking break is released again (e.g. off) the process repeats starting with step 1C.
Some people, no names mentioned, forget to put a car on the parking brake. If at the time of power-on
the parking brake was released (e.g. off), the normal power-up reset will happen (step 1A), however
relay-A and relay-B will not have been activated. If after ~3 seconds (the reset time) AND before driving
the parking brake is pressed (on) , process 1D will happen and an unlock signal will be sent to the car.
This is normal behavior. What is NOT normal behavior is NOT using the parking-brake
.
