PCM warning light questions

[CamaroChris]

I am going to rework the harness on my 6.0l this weekend. Harness/ PCm are out of a 2000 Yukon XL. What I want to know is if these warning light wires from the PCM for Low oil, Low coolant and so on are just a 12v power switch. Can I use all of these senors and build like an L.E.D panel that will light up to give warning? I have an ls1 camaro and those warning lights have saved my ass a few times. My goal is to make my truck just as functional as a bran new truck. I would buy a new truck but I do not want a loan, I pay cash for everything Plus I like my suburban more so I'm not really looking to make a 4 wire stand alone system I want to integrate this drive train into my truck like it was supposed to be there factory. Also how do I wire the A/C in the truck. Do I just wire the 6.0 compressor to the factory wiring or do you control it through the PCM?

[BR3W CITY]

The cel light is just a single wire (and ground) 12v connection that should be off of the harness directly.
I'm not running any other warning lights besides the CEL; I've never had one come of for the correct reasons, or tell me something I didn't know. The low oil level sensor doesn't come on until WAY too low, even by that time you've been low on oil for a while...or there is a major leak.

I feel the same on low coolant level as well, because the engine temp would reflect a lack of coolant, often before the sensor got to that level.

I have had 3 oil level sensor failures, and a coolant temp light that would do whatever it wanted, and a brake fluid level sensor that also went cowboy on me. Seems like they just give you more to panic about. Check your oil level at fillups or at least before a longer trip, especially if you run change intervals longer than 3-4k miles.

Get something like a scanguage II, Aeroforce Scangauge, or smartphone enabled OBD connections that allow you to real time monitor all gauges AND pcm warnings. If you really want to have your eye on everything, these will give you access to do so.

[usmcchevy]

I'm pretty sure the only light the PCM has dedicated output for is the Check engine light. All the others run off of serial data. I guess you could use the gauge cluster out of the Yukon, might need the BCM too. Havent touched my AC yet.

[TR65]

Chris,

I use a scangage II like BR3W City said and you can display 4 gages of your choice at once.

I did an LED panel something like what you are talking about. For most of the warnings if they are not on the serial bus, the ECM grounds the connection.

Here is a thread on the panel I built. All but a couple of the lights are functional now. There are some pictures of it operational in the A/C thread below.

http://67-72chevytrucks.com/vboard/s...d.php?t=360205

The ECM should control the A/C for you. You just have the A/C control power the A/C request line on the ECM, check the schematic for your particular engine. The late model ECM's have the A/C request on the bus so that complicates things. Here is how I fixed mine.

http://67-72chevytrucks.com/vboard/s...d.php?t=468107

TR