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APX 4500 & J2 rear connector

Posted: Thu Mar 07, 2019 12:55 pm
by blackwater
So I have a firetruck that on one talkgroup when the radio is turned on it goes into emergency mode automatically. This radio was installed previously by someone else and didn't put the rear connector on it. My question, if I pull the pins from the ignition sense side can I still use just the pins in position 14 & 15 and the radio not look for ignition sense power?

Re: APX 4500 & J2 rear connector

Posted: Thu Mar 07, 2019 3:43 pm
by com501
Why not just put the correct connector on the rear of the radio and be done with it? The connector comes with the EMER jumper installed, plus an ignition sense lead and speaker connector.

Re: APX 4500 & J2 rear connector

Posted: Thu Mar 07, 2019 4:03 pm
by blackwater
I’m looking at using the connector that came with the radio. I’m asking if I pull the connector apart and remove the ignition sense wires and just leave the jumper will that work? If they turn the main power on in the truck the radio needs to turn on also and it does until I put the connector on it. I’m trying to side step hooking up the ignition sense if at all possible.

Re: APX 4500 & J2 rear connector

Posted: Thu Mar 07, 2019 4:25 pm
by com501
If you want it to come on with the key, you must wire the accessory igntion sense.

Re: APX 4500 & J2 rear connector

Posted: Thu Mar 07, 2019 4:28 pm
by com501
If you are turning on a battery switch, the ign sense must be wired to the switched side of the battery switch. The high current red lead and ground must remain hot to the battery at all times. II am assuming you have a dash mount, otherwise all those functions would come from the control head. The radio should be programmed for ignition only.

Re: APX 4500 & J2 rear connector

Posted: Fri Mar 08, 2019 7:53 am
by blackwater
Thanks. I was hoping I could just remove the ignition sense and speaker wire and pull the pins out of the connector and just keep the jumper that is in 14 & 15 connected and it would work.

Re: APX 4500 & J2 rear connector

Posted: Fri Mar 08, 2019 11:50 am
by Jim202
blackwater wrote:Thanks. I was hoping I could just remove the ignition sense and speaker wire and pull the pins out of the connector and just keep the jumper that is in 14 & 15 connected and it would work.
Before I make a comment on this, let me say that it might help if you spend a few minutes reading the installation information on this radio.

If you have a control head, you would normally have a speaker near it. The speaker connections come from either the control head directly or from the accessory connector. This is dependent on the type of control head and if the radio is a dash mount or trunk (remote) mount radio.

The emergency condition is normally taken care of by a remote, normally closed switch, or with the jumper installed in the accessory connector or shut off the feature in the radio software.

The radio can have the accessory power up feature set in software to use the accessory ignition connection from the accessory connector. You can also set the software to only go off and on from the control head power switch. In some control heads it may be required to move some jumpers around to control the radio on / off with the power button.

This is a good place to ask questions on your radio install. So if you have more, just ask away.

Jim

Re: APX 4500 & J2 rear connector

Posted: Thu Jul 04, 2019 9:39 pm
by VE3HKB
I know this sounds silly, but having read the installation manuals I am still confused.

For a dash mount APX,with an O2 control head, that is programmed to use the front red emergency button, having the accessory cable plugged into the rear accessory / J2 connector is necessary, both for ignition sense (25) and shorting the emergency pins (15 & 14).
This appears to be clearly shown in the drawings.

However, for a remote mount APX with the same O2 control head and having the front emergency button enabled, is the Accessory connector still required? I would think YES, as the drawings show stuff connected to what appears to be the accessory connector at the back of the control head (although it looks like is is on the wrong side). But this would mean that the ignition sense would be duplicated - once from the PWR/SPK connector, and once again at the Accessory connector. The drawings are less clear showing where the SINGLE ignition sense wire originates. To me it has to be the PWR/SPK as it is a yellow wire. The thin red wire from the accessory cable is missing / not shown.

Confusing me even more is the fact we now have two Accessory connectors - on on the rear of the radio chassis and on at the rear of the control head. I always thought these two connectors were identical even though they are physically separated.

My interpretation is that if the emergency button is programmed, you need to short out the emergency pins at the Accessory connector (J2), or have an external switch connected - either way the pins need to be shorted so as not to continuously declare (emergency) as soon as the radio is turned on.
If using an external switch, you pick the Accessory connector closest - for dash mount there's just the one (J2 / rear); for remote mount, likely the control head.
However, for ignition sense, only one is required. Again, for dash mount, rear accessory connector. For remote mount, ignition to the accessory connector is not required as it is already supplied to the PWR / SPK connector.

Does this makes sense?
For shorting the emergency input (15 & 15 at J2) does it matter which accessory connector is used?