thank you, gents!
In such a rainy day, I didn't get a chance to fully test connections but I did test the trailer side according to the plug diagram (trailer). Several Ohm(resistance) can be measured at each pins(for lights) except Pin4(aux 12V) has 12V output, which I believe it comes from the battery. Is it correct? When it connects to the vehicle, the Pin4 connects to vehicle's pin4 that is 12V too. Does it the mean the battery on trailer get recharging from the vehicle?
At this point, I feel no issue from trailer. I will test the vehicle side later. Usually I will test the voltage output at each pin while giving the relative function but I don't know how much voltage it supposes to be for the L/R turn light(pulse?), stop lights, running tail lights and break signal. If there's a bad ground, I should read lower voltage or nothing?
Thanks again,
Daniel
