Mazda CX-9 - Page 9

Automatic door-lock/unlock CX-9 /2007 Version 1.0 Page 9
Third check: Relay-B should pulse.
o Make sure Black wire is connected to MIN
o The Red wire is connected to + 12V
o Locate Relay-B make sure you can see it well.
o Hold the white wire against the MIN (simulating the parking-brake switch)
o Relay-B should activate and after 1.5 seconds de-activate. If you now remove the white
from the MIN, Relay-B should activate and after 1.5 seconds de-activate again.
o Repeat it a couple of times. Every time you hold /remove the white wire, you will hear
every time 2 relays: A and B. Concentrate on relay-B
o If Relay-B did activate and de-activate, you are fantastic if NOT.. oh well.. you are still
great
 Check the circuit. Are the wires on the right contact points on contact-C
 Is the capacitor correctly connected (with the – connected to the MIN)?
 Do you still have 12V?
Fourth and last check: Making sure that Relay-C is LONGER activated than Relay-B at power-on.
This requires 2 pair of eyes and you only have 1 pair, but it can still be done. NORMALLY if the
capacitor C1 (2200uF) is two times the capacitor C2 (1000uF), this should not be a problem, but
if you have old capacitors, they tend to dry out and lose their power.
o Make sure black wire is connected to MIN
o Make sure the white wire is also connect to MIN (simulating the parking-brake switch)
o Locate Relay-B and Relay-C. Make sure you can see them.
o Hold the red wire against the +12V (simulating power-on)
 Relay-B should activate and after 1.5 seconds DE-activate.
 Relay-C should have activated at the same time as Relay-B BUT will de-activate
later (if it is quite you may be able to hear the click)
o OK.. now remove the red wire from the +12V and hold the red wire against the MIN (de-
charge C1 and C2). Relay-B and Relay-C will activate and de-activate and against Relay-C
should take longer.
o ARE U SURE.. ??? NO.. repeat by holding the red-wire against the +12V and repeat he
whole test
o If relay-B and relay-C activate and relay-B de-activates before relay-C, you are gigantic
and you should consider starting your own business if not.. keep your day-job and
 Check the circuit. After the wires on the right contact points.
 Is the capacitor correctly connected (with the – connected to the MIN)?
 Didn’t you switch capacitor C1 and C2
 Are this new capacitors, if not they might have dried out and lost their power