old installer, old truck, jog my memory?

Folks- I used to install professionally in the early 90's. I am now a computer network engineer. I have a 1989 S10 Blazer (mine) that I finally got around to repairing the power door locks and windows on so I can finally install a remote start- which of course will require an alarm. I have a Hornet 740T, going to install it with an Avital 4003L add-on remote start. I will at some point in the future add a window roll-up module as well. I don't have the 4003 or the window module on hand, but if I recall, these will be triggered by the alarm's Aux channel. I could probably just set the window module to roll-up the windows on arm, anyway, as I don't ever leave them down. I have the factory power door locks repaired (replaced jamb switches as well) which basically consisted of replacing both power door lock switches and lubing the heck out of everything in the door to free up the mechanisms. What I am having trouble with, though, is trying to dust off some neurons and identify the type of door lock switching done in the 89 S-10 Blazer. I have read the articles here but it's not making much sense to me, as it's been a long time. I THINK I have a Reversing Polarity system ("Type C" as it's identified in the manual), but the identification matrix in their manual seems a bit sketchy, requiring cutting wire, testing, and trying other wires. I don't want to be cutting too many wires for the sake of testing. I am fully comfortable with vehicle modifications and electronics, and will test what I am told here- but I could use a point in the right direction so as not to have to reinvent the wheel. Thanks in advance for any assistance!!

Directechs says its a 5 wire .triniforever

Thanks very much! In looking at the old switches, this would seem to be true. I will test of course, but now I have a better idea of the kind of behavior I should expect.

The 1st gen S-series is my strong suite. I currently own 5 of them. Yes it is a 5-wire. Easiest place to intercept the lock wires are on the drivers side kick, above the park brake, next to the fuse box, where they come out of the body. Black and dk blu wires.

Here is a good reference on door locking systems to keep handy...   https://www.the12volt.com/installbay/file.asp?ID=708Soldering is fun!

Thanks gents. While I am a "solder and shrink, not crimp" kinda guy, I have elected to use the single-wire tap connections that bite through the wire for the door lock integration in this application. Yes, a bit lazy- but given that they're not a critical juncture and they are going to be a bit hard to get a soldering iron into, this will work. Worse case, if someone does start tampering they'll just be able to disable the door lock integration. Everything critical will be hidden, soldered, and heatshrunk, with factory loom and dress. End of the day, it's still a 25-year-old daily driver, not by any means showroom stock or valuable. The alarm is being added for ease of integration of more modern features (keyless entry, domelight supervision, etc). DaveP- you sound like you might be into these old trucks as much or more than I am. I have a solid axle swap under mine, using Rodeo D44 rear and Wagoneer D44 front. Expect a PM. :)

OK, so here's a question I probably ought to know the answer to, but can't recall: I have the Hornet 740T (probably the same as some model of Viper, but I haven't been bothered to look and see)... It has a pinswitch input of course, to trigger the door. This is H1/5 (negative trigger, pinswitch. Green wire) There's also an output for the Domelight - H1/4 (200ma -, BLACK/ white). Now being that my pin switches are negative, and trigger the domelight via ground ... if I attach these two circuits to the same lead I see problems being possible. How should I connect these to apply this functionality: -domelight is triggered as factory, when opening the door. -opening the door triggers the alarm -domelight illuminates on disarming the alarm. I realize this is a really simple circuit, and some folks are going to say "thought you were a professional installer?". Yes- years ago in my early 20s, I am now in my early 40s- literally half a lifetime ago, I was. While I did a bunch of S10s and GMs back in the day, I am far removed from that day now. Help an older guy dust off some neurons here.... :)

Well, it's a damn good thing I didn't just go ahead and tag 12V into that wire like I was going to.... I stopped to read the document you guys linked to while I am sitting at the kitchen table doing some subassembly work (relay packs and such), and it looks like I MUST cut the wires, and lock side goes to terminal 87A, while door lock solenoid side goes to 30... 12V constant supplied to terminals 85 (to run the relay) and 87 (to give source 12 to the solenoid when it's triggered. This is precisely the sort of thing I posted here for. Again, many thanks, folks!

... all of which means, now that I look at my relays, I need to find some bases that have a NC wire in them (I stripped out the 87a contact years ago when I ordered a bulk shipment of relays off ebay, as I couldn't imagine ever needing them. Dumb!) Luckily, I ordered another couple dozen of those 5-wire relay interlocking bases with relays, last week. :) I know there's probably a link somewhere, but a quick glance hasn't found it... someone want to point me to the "donate" button so I can throw some cash into the pot to keep the lights on around here? It's the least I can do as you guys just saved me a couple expensive new door lock switches I just replaced on the old heep. :)