Jsdirt

I'm not sure how it's done. I've heard of something called Carprog that can reset it. The dealer will tell you to buy a new one, but there are people out there (and devices) who can reset them. Once a crash is detected, whether it was in a crash or not, the module locks and cannot be reset with regular scan tools.

Yep, that be the one!

Best thing to do would be to get ahold of a wiring diagram, and see if there is a common 12v feed for all these different items. A friend of mine just posted a video on a Dodge Ram with a similar issue, that was traced to a bad ignition switch. On that vehicle, in the run position, there are 2 wires supplied with 12v - one of them had 0 volts intermittently.

Should be able to remove the HID bulbs and install LEDs. Current draw will be a bit less with LEDs, so wiring should handle it. I'd imagine you'd have to eliminate any ballast in the system. Just a quick search turned these up. I have no experience ordering with this company - just posting the link for reference, so you can see what they look like. I'd recommend shopping around first: https://www.headlightexperts.com/carfinder/?find=2017-gmc-yukon-w-hid-h-l-537937 Looks like you'll probably have to install "warning cancellers" to prevent warning messages from appearing in the cluster after the conversion.

I found the build sheet of my '72 El Camino above the gas tank. It was in rough shape, so I probably missed the "broadcast" labeling, since half of it was illegible, or missing.

Ahh, thanks for the info, Mike. In all the years I've been around cars, I've never heard that term "broadcast" when referring to RPO codes. Good to know.

Those look like RPO codes to me. The RPO code list should be on a sticker inside the glove compartment.

Without being there in person to see exactly what it's doing, and testing things, I can only give you a WAG (wild-assed guess). If it were mine, I would clean the throttle body all around the butterfly of built up carbon. If that didn't change anything, I'd test the throttle position sensor for proper function - the fact it was replaced recently makes that instantly suspect to me. EGR function would also be suspect - if it's leaking at idle, this will cause stalling. Last on the list would be removal, testing, and cleaning of the idle air control valve, Injector spray pattern (with timing light), and a fuel pressure check.

There should be a gasket and a big o-ring there, like this: https://globaltransmissionparts.com/4l60e-4l65e-4x4-extension-housing-gasket-seal-kit-1998-up-15724744/?gclid=EAIaIQobChMI4dXngceO6gIVTL7ACh14UAtzEAQYASABEgLbxPD_BwE If nothing was there, it's possible someone slapped that trans together before you owned it.

Years ago I had a lemon of a '00 GMC Jimmy - worse than the Silverado if you can believe that one, but I digress. This one was losing tranny fluid with zero external leaks, and the transfer case was at the perfect level every time it was checked. Wasn't until I got so sick and tired of the constant failures and decided to dismantle and part out the vehicle, did I find the fluid was passing though a failed 4x4 switch, and getting drawn up into the vacuum lines, filling up the vacuum canister, and eventually being drawn into the intake and burned! Only when I removed the vacuum canister and it felt much heavier than it should, was the problem revealed. All the lines up to the intake were coated in ATF! Another fantastic engineering brainstorm courtesy of GM ... General Mess ...

That's what I always do. Get a worm clamp, or better yet, a "fuel injection hose" clamp - a little better quality, and grabs in a full circle around what you're trying to clamp, with minimal gaps.

Oh, those stupid black connectors? Common problem on these trucks going all the way back to the 90's (then, it was the plastic insert on the other end, on the intake manifold). I usually just break the stupid things off, and clamp the hose to what is underneath. Fits perfect, and cheaper than buying another heap of plastic that will fail the same way eventually. Just break that outer shell - not the whole connection.

There's a leak somewhere, in that case. Probably small if you can't see it dripping anywhere. It could be running down the back of the engine and evaporating, or out from one of the heads, or a pinhole in a hose. You'd have to have it warmed up and the hoses nice and hard with pressure, then crawl around underneath with a good flashlight. If it still has the orange Dexcool in it, you'll see dark orange crust wherever the leak is, especially if it's been happening for a while.

You're welcome. Have fun on the trip! When I question whether a thermostat is working or not, I'll fire up the engine first thing in the morning with the hood up, and feel the upper hose, cylinder heads, and t-stat housing and note the temperatures as they warm up. If the upper hose immediately gets warm, the t-stat has failed, and is leaking flow past it. If the heads seem to get hotter than I was expecting, I throw the infrared thermometer at it. 210° plus or minus is what I want to see. Anything much over 240° and I start to get concerned. Nearing 260° I'm frantically feeling around for where the problem might lie, so I can shut the engine down quick. If the upper hose is hot but the radiator is ambient, along with the lower hose, then I suspect the pump isn't pumping. The heater hoses should warm up first - usually if both are warm quickly, then the pump is working. The gauge in the cluster typically reads 210° , needle straight up, but the actual engine temp varies between 185° - 230° with little movement of the needle, according to the temp sensor reading in the scan tool. Bottom line, as long as the engine isn't literally smoking hot, you're fine.

Most modern transfer cases take ATF. Perfectly normal, as is the giant blob of metal shards stuck to the magnet after it's first ever oil change. They should be sealed. If the transfer case fluid level is over and above the fill hole, then it's leaking from the transmission. That's why you should always remove the fill plug first, before doing an oil change.