Electrical gremlins - dome light and alt

[dhcomp]

Ok, so i installed a remote start a couple months ago.

Works fine, almost.

Recently, its been setting the alarm off after running for 5 or 10 minutes. No shock to teh vehicle, and its supposed to bypass the shock sensor when its running anyways.

Questions is this: When hooking up the ign and acc wires to this unit, however i did it, it doesnt' turn the radio on when it is running remotely. Which is fine with me. Ign works, lights work, Hvac works.

Where is the alternator signal that tells it to charge hooked up? Is there a chance its not charging when started remotely, due to how i hooked it up? This woudl cause the voltage to drop after it ran for a couple minutes, which may cause the alarm to go off. If i disarm/rearm teh alarm, it normally goes off once more immediately.

Next question:
Dome light. When the rear window is lowered, and then the tailgate opened - is the dome light supposed to go on? THe dome light triggers the alarm, and i want to make sure that if my rear gate is opened, it will set it off. The passenger side has a plastic damper thing in the jamb that looks like a switch, but IIRC, there are no wires going to it when i pulled it out. But i forget Any advice?

 

[dremu]

Ok, so i installed a remote start a couple months ago.

Works fine, almost.

Recently, its been setting the alarm off after running for 5 or 10 minutes. No shock to teh vehicle, and its supposed to bypass the shock sensor when its running anyways.

Questions is this: When hooking up the ign and acc wires to this unit, however i did it, it doesnt' turn the radio on when it is running remotely. Which is fine with me. Ign works, lights work, Hvac works.

Where is the alternator signal that tells it to charge hooked up? Is there a chance its not charging when started remotely, due to how i hooked it up? This woudl cause the voltage to drop after it ran for a couple minutes, which may cause the alarm to go off. If i disarm/rearm teh alarm, it normally goes off once more immediately.

Mmm. The quick answer is that the alternator is fed by a switched ignition source. In theory if the ignition is on, the alternator should be charging. Sounds like your remote start/alarm thing isn't turning on the accessory, just the ignition, which should be fine.

Anyway, it's easy to test. Start the truck up with your gizmo and check the battery voltage. If it's less than 13, the alternator's not going. You can test it more accurately by checking the battery voltage with the motor off (should be ~12) and with the motor started by the key (should be 13.5-14.)

Next question:
Dome light. When the rear window is lowered, and then the tailgate opened - is the dome light supposed to go on? THe dome light triggers the alarm, and i want to make sure that if my rear gate is opened, it will set it off. The passenger side has a plastic damper thing in the jamb that looks like a switch, but IIRC, there are no wires going to it when i pulled it out. But i forget Any advice?

Assuming this is a Burb, then yeah, the plastic gizmo by the tailgate is a dome light switch. Should be one wire as it grounds to the body. Blue, IIRC, and short so if you yank the switch out, the wire gets lost in the body and you have to fish it out, sparking all the way as it makes contact with grounds. BTDT.

-- A

 

[dhcomp]

Mmm. The quick answer is that the alternator is fed by a switched ignition source. In theory if the ignition is on, the alternator should be charging. Sounds like your remote start/alarm thing isn't turning on the accessory, just the ignition, which should be fine.

Anyway, it's easy to test. Start the truck up with your gizmo and check the battery voltage. If it's less than 13, the alternator's not going. You can test it more accurately by checking the battery voltage with the motor off (should be ~12) and with the motor started by the key (should be 13.5-14.)



Assuming this is a Burb, then yeah, the plastic gizmo by the tailgate is a dome light switch. Should be one wire as it grounds to the body. Blue, IIRC, and short so if you yank the switch out, the wire gets lost in the body and you have to fish it out, sparking all the way as it makes contact with grounds. BTDT.

-- A

Cool, thats helpful. Guess in need to find that ground wire then.

 

[dremu]

Cool, thats helpful. Guess in need to find that ground wire then.

Uh, just to be clear, it's not a ground wire. One side of the switch is grounded by being screwed into the body sheet metal.

The other side goes to the dome light and then to the battery, so the wire at the switch is "hot" (admittedly through the dome light) all the time.

If you ground that wire, the dome light will always be on

It's ... umm, negative switched, in alarm parlance.

-- A

 

[dhcomp]

Yah, i got it. Thats kinda what i meant. I'll check it out. If it was hanging in the body though, id expect my light to flicker. It doesn't. I'll see what i find tonight.

 

[lectric80]

Unless they changed the colors, that switch wire for the dome system should be white. Every one I have worked on had the orange wire for the dome system as the constant hot, and the white as the switched ground. At least on the GM's I have dealt with.

 

[JDNobodi]

Do you have the key on when you do the remote start? If not the alt is not charging till you get inside your vehicle and turn the key.
The ignition switch is switched to multiple circits, so the alt could not be connected to the ingtion circit. On my late 70's harness it isn't. The alt exicte wire is actully wired to HAVC system.

 

[dhcomp]

No key in during remote start. Thats the point, isn't it?

My HVAC works when started remotely.

But yah, thats what im thinking, stereo isn't on, maybe alt isn't either.

We'll see. It worked fine when it was set to run for 10 min. Now set to run for 20 min. It seems to be setting itself off more often. I'll look at it this weekend.

 

[dhcomp]

Ok, quick diagnostic this weekend.

When running on remote start, battery gauge shows over 13 (14 range), and doesnt' change when key is turned on. So it looks like ALT is charging.

Rear tailgate wire deal is corroded to ****. Need to replace plug, and see if that is the problem, or if i need a new switch. Scraped crap off plug contacts and grounded to body, and it functioned, so now i just gotta make the whole system work.

 

[dhcomp]

Tried to clean up that rear tailgate jamb switch, no luck.

Does the blazer have this switch, or just the burb? Any source for this part? LMC doesn't have it, or know what i am talking about it.

 

[dremu]

Blazers don't, no, 'cuz their domelight doesn't come on with the tailgate.

I seem to recall getting one from the dealer, way back when. I don't remember it being stupid expensive, like, I donno, ten bucks or so.

-- A

 

[lectric80]

Nope no such thing on a Blazer. I just set up a switch back there to allow me to turn on the dome from the rear.