Domelight Supervision Not Triggering Relay

So I'm installing an avital 5303L into a 1981 cherokee. I've got every function working properly except the domelight supervision. My car's domelight is a single terminal negative trigger. I ran the 200ma negative signal from the alarm to pin 85 on the relay. Pin 86 is 12v constant, pin 87 is ground and 30 is to the domelight wire. I cannot for the life of me get the alarm to trigger the relay. I have verified the alarm is sending a negative signal with a volt meter. I even tried adding a transistor based on a diagram I found here but still no luck. I'm at a loss at this point and this is the last piece of wiring for me to complete. Please help. Pic 1 is my first transistor circuit attempt that did nothing. Pic 2 is my second circuit attempt but using the transistor to trigger the positive side of the relay. Still nothing.

Guess I should mention I have verified the relay works and tried two known functioning relays. Also, like I mentioned the keyless entry works, the remote start works, the shock sensor works...all of it works but the stinking domelight and it's killing me. Adding a better pic of circuit 2 since it was so dark.

Is it a 1981 Chief or 1991 Cherokee? What color is the output wire from the alarm brain that you are using? What color wire are you connected to in the Jeep and where are you locating the wire? Is it the same wire you are connected to for door triggers for the alarm? How did you manually test the relay?Steve G

Notice that all connections on my diagram are negative. Negative from alarm brain, ground to center conductor or case of transistor and ground output from the emitter. You need to ground the center leg and apply power to 86 of the relay.

iskidoo wrote: Is it a 1981 Chief or 1991 Cherokee? What color is the output wire from the alarm brain that you are using? What color wire are you connected to in the Jeep and where are you locating the wire? Is it the same wire you are connected to for door triggers for the alarm? How did you manually test the relay?

The Chief was a package on the original Cherokees. It's a 1981 Cherokee with the Laredo package (electric locks and adjustable mirrors...fancy :D) . The alarm output wire is black with a yellow tracer. The domelight wire is black and directly connected to the single terminal door jamb switch. I do not currently have the alarm's door trigger wire (green) connected as I try to resolve this issue. At first I did have the two wires (black w/yellow & green) connected together and run to the cherokee's domelight wire. I had the relay wired as listed in the previous post but instead of pin 85 going to the signal wire I directly grounded it to a body ground.

i am an idiot wrote: Notice that all connections on my diagram are negative. Negative from alarm brain, ground to center conductor or case of transistor and ground output from the emitter. You need to ground the center leg and apply power to 86 of the relay.

I tried that setup and it did not work for me. It's actually the first thing I tried. Edit: if that's the solution that's worked I'll give it another go. I'm still not sure how a transistor is working with only grounds operating it since the data sheet suggests it works off a voltage differential but I'm far from being an electronic wizard. I'm barely a hack and I'm sure y'all know infinitely more than myself. :D At this point I'm ready to try any solution as I just can't seem to figure it out and that bugs the crap out of me.

When you tied the 2 wires directly to the door trigger it's likely that you may have damaged the dome light output. You say you tested it for a negative output. proper way to test for a (-) signal in a normal +12 volt vehicle with a Digital Multimeter is as follows. Set DMM to 20 volts DC range Connect Red test lead to +12 volt constant source Connect Black test lead to suspect wire When the (-) signal is present, the DMM will show +12 volts. Kind of inverse logic but it works. [from user Kreg357]Steve G

I did exactly as you said and get 12v reading on the dmm. I can see when the alarm sends the signal and when it turns off after 30s.

Is it a typical aftermarket spdt 12 volt automotive relay? If you trigger it using the trunk output does it trigger the relay as it should?Steve G

iskidoo wrote: Is it a typical aftermarket spdt 12 volt automotive relay? If you trigger it using the trunk output does it trigger the relay as it should?

Yup regular ol autozone relay. 30amp 5 pin relay. I'll try the trunk lead tomorrow when I'm in the shop. I also ordered an ssr that should require less power to trip that I'm hoping arrives tomorrow.