Compustar install driver's door issue

[Sino]

My brother's installed an alarm/remote start in my EX sedan. We tapped into the dome light wire at the passenger kick panel for the door triggers. Both of the passenger doors function fine for the alarm, but as soon as you kill the ignition and open the driver's door, the power lock button stops functioning and the open door stops sending a signal to the dome light. Strangely, opening the driver's door also stops the rear driver's side door from signaling for the dome light to light. This also causes the aftermarket alarm LED to light solid. The convenience lights on both doors work fine.

One thing we did in the install is we didn't use the factory arm/disarm wires from the aftermarket alarm, rather we used factory hood switch for the aftermarket alarm, and bridged the wire so the factory alarm never arms. I'm wondering if this method of bypassing factory alarm may somehow be causing this, or if it's something else we've overlooked. Any points in the right direction would be awesome.

 

[xci.ed6]

unhook the dome trigger and see if they work.

 

[lashlee]

I would guess that the OEM alarm is sensing the door movement without being disarmed and shutting down the car. I would try to tap on to the disarm wire and re connect the hood pin like normal and see what happens.

 

[Sino]

After it worked normally for a brief time this morning, we took apart some panels and came to narrow it down some more. A clue is that while the key is ON, the dome light functions just fine with all doors. It seems like once the key is out the driver's multiplex is losing power, which seemingly explains why the convenience lights still work, the driver's power lock switch doesn't, and the rear driver's side door stops lighting the dome light as well. Tomorrow we're going to double check the 2nd ignition and accessory wires for the alarm to see if there's anything wrong, but I'm much more confident today. I was really worried the multiplex had fried.

 

[Sino]

What a pain in the *** this has been. Latest discovery is that when I disconnect the drivers door panel connector for the window switch, I get no more flicker in the dome light and the dome light goes on and off correctly with each door switch. Disconnecting the main power connector on the alarm module also corrects done light issue, but drivers power locks remain borked. Those only work with key in ON.

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[james'99]

What a pain in the *** this has been. Latest discovery is that when I disconnect the drivers door panel connector for the window switch, I get no more flicker in the dome light and the dome light goes on and off correctly with each door switch. Disconnecting the main power connector on the alarm module also corrects done light issue, but drivers power locks remain borked. Those only work with key in ON.

Sent from my Galaxy Nexus using Tapatalk

Have you tried resetting the multiplexer/unhooking the battery for a bit?

 

[Sino]

Tried both with no success. Probing upstream from the power lock switch we discovered that there's no power at fuse 13, which should be hot at all times. Based on the symptoms (windows all work, as do power locks only via alarm remotes (both of which are via the passenger's multiplex), it seems likely the driver's multiplex took a dump. Ordering one from ebay to test.

Something my brother found online about how the factory radio's illumination dimmer wire doesn't actually draw full voltage worries me. He's guessing it's possible that the aftermarket HU draws more power through that wire than the multiplex likes and ended up frying it. I also put in a flasher relay for LED turn signals and afterward it lit up the turn signal indicators on the cluster whenever my parking lights are on.

In conclusion, I hate electrical.

 

[xci.ed6]

weird, got any electrical diagrams?

 

[Sino]

yeah I've got the honda service manual and ALLDATA

 

[Sino]

Looks like it's finally sorted. After having bought a driver's multiplex off ebay, installing it to no avail, I started poring over the service manual for diagnosing the multiplexers. There's actually a really cool diagnostic mode for driver's and passenger's that you can get to just by fashioning a jumper wire (though there's also a cheap special tool, SCS connector.) It essentially beeps the speaker and flashes the ignition light whenever you hit a switch that ties into the multiplex (door locks, windows, door switches, seat belt, lighting/wiper stalk) so you know that the signal's getting through. Then testing, as per the manual's suggestion, the wires on the door multiplex, we came to find the issue, and it was self-inflicted. In the pursuit of replacing the factory alarm LED at the lock pin with one wired to the aftermarket alarm, to avoid splicing at the door and having to feed it through the conduit, we spliced it already inside the car. Unfortunately that was upstream of the factory splice (red circle in diagram below), which leads down the door multiplex.

So robbing the door multiplex of power caused all those issues with the power locks and door switches. I learned so much chasing this gremlin lol