WTF?

MarkW65

New member
I'll apologize for the long post first but I'm a bit baffled as to what has happened.
I was driving to work and suddenly my AC didn't feel cool. I looked and the AC button was not lit up so I hit it, it flashed and went back off. I hit it again and it did the same thing again.
It's an '09 that I've had for 3.5 years and I wrote it off to needing a recharge and took a mental note to look into it later.
About 5 miles later my truck started "dinging" at me and the dash said I needed to service stabilitrak. WTF?
Then ""service traction control" with the light showing on the dash. Then "overheating. idle engine" The truck barely had power to pull away from the traffic light I had stopped at but then seemed to pull away normally. Next was the warning that the AC was disabled due to overheating. I was trying to get far enough to get pulled over safely and another warning "overheating. decreased power". Finally got pulled over and sure enough, coolant was leaking out. I let it cool for over an hour while I met with a client that was nice enough to pick me up and help me out. Bought some coolant to put back in it hoping I could limp it home to check it out. Didn't get very far. Towed it home and let it cool for a while.
The only thing I could see is the bottom radiator hose was wet around the neck. I bought a new one and removed the old. Neck and radiator looked good. No rust or cracks that I could find BUT I also couldn't find any cracks or holes in the hose. The only thing I wonder is if the clamp had lost it's grip since it broke easily when I removed it. Everything else looked good as far as I could see.
I put the new hose on and no leaks. No overheating. Truck was quitting after starting the first couple starts though.
BUT traction control, light, service traction control warning, and service stabilitrak warning, and engine light were still showing. I also noticed my engine hours had reset to zero and the outside temperature was showing as 55 degrees (I WISH!). I tried my AC and it was working again EXCEPT it was cool on the right side of the truck and blowing hot on the left side of the truck.
I shut it down, finished putting my air filter box back together and unhooked the battery again to see if it would clear warnings.
Went out after dinner and hooked the battery up, started fine, let the truck run for a bit, took it for a test drive. No leaks, no overheating, no warnings or lights, no engine light.
BUT the engine hours are still reset, now showing only the mileage from my test drive, my AC is still blowing cold on the right side of the truck and hot on the left side, and it still says it's 55 degrees outside.
I have a theory/suspect cause but I'm hoping an owner or mechanic has experienced this and can tell me precisely what's going on.
Thank you in advance for any help getting my truck straight. It's been a great truck to this point with no major issues and I've kept it maintained religiously. Hoping to keep it.

2009 Sierra 4x4 1500 5.3 flex
 

MarkW65

New member
SOLVED
I assume that the computer was shutting things down because of overheating at first but was not sure why all the problems after I got the new hose on.
I think I left out the part of the story where I had my emergency flashers on since I barely got it off the road. When I came back the battery had died. I now believe this is what caused my other issues once the hose was replaced.
I did some research and found that the computer needed to reboot after the battery died like that and how to do it. Took care of all my warning messages and lights, fixed my AC and my truck now starts and runs as it should.
I'll share what I found. I did this and it worked.

Disconnect the negative battery cable for 10 minutes. Re-connect after 10 minutes.
Turn the ignition on for 1 minute without starting. During this time, do not touch or adjust any controls.
After the 1 minute, start and let the engine run for 5 minutes. Touch/adjust nothing!
( I sat in the truck this whole time and didn't even open the door.)
Then take off and get on a road where you can drive above 45 mph as soon as possible.
This reboots the computer and allows it to correctly calibrate all systems.

I noticed during my 1 minute of key on/not running that the climate control cycled itself through the vents, defrost, floor. That was my first clue that something was happening and I may be getting somewhere. When I started the truck and let it run for 5 minutes, it set itself on 74 degrees and was blowing cool air from all vents (YES). No warning lights or messages. Started and ran smooth. The only thing I could see wrong is that the outside air temp still read 55 degrees when in reality it was upper 70s.
After my 5 minutes, I took off and jumped on the highway. I drove to the first exit and turned around to head back. Just before I got to my exit I noticed the outside temp had gone up to 61 so I drove on by my exit hoping it would keep climbing thinking this may be the computer getting systems adjusted. Seems that was the case. By the time I got to the next exit it was reading real outside air temp. I turned around and headed back. I touched nothing until I got back home. Adjusted my AC andd cranked it. SUCCESS!. I've since been out and made some stops. Everything is normal except engine hours. I read that this is a common problem and those won't come back so now my truck with over 140,000 shows that it has only run for a bit over an hour. Who cares! Got my truck back to normal otherwise.
 

MarkW65

New member
SOLVED
I assume that the computer was shutting things down because of overheating at first but was not sure why all the problems after I got the new hose on.
I think I left out the part of the story where I had my emergency flashers on since I barely got it off the road. When I came back the battery had died. I now believe this is what caused my other issues once the hose was replaced.
I did some research and found that the computer needed to reboot after the battery died like that and how to do it. Took care of all my warning messages and lights, fixed my AC and my truck now starts and runs as it should.
I'll share what I found. I did this and it worked.

Disconnect the negative battery cable for 10 minutes. Re-connect after 10 minutes.
Turn the ignition on for 1 minute without starting. During this time, do not touch or adjust any controls.
After the 1 minute, start and let the engine run for 5 minutes. Touch/adjust nothing!
( I sat in the truck this whole time and didn't even open the door.)
Then take off and get on a road where you can drive above 45 mph as soon as possible.
This reboots the computer and allows it to correctly calibrate all systems.

I noticed during my 1 minute of key on/not running that the climate control cycled itself through the vents, defrost, floor. That was my first clue that something was happening and I may be getting somewhere. When I started the truck and let it run for 5 minutes, it set itself on 74 degrees and was blowing cool air from all vents (YES). No warning lights or messages. Started and ran smooth. The only thing I could see wrong is that the outside air temp still read 55 degrees when in reality it was upper 70s.
After my 5 minutes, I took off and jumped on the highway. I drove to the first exit and turned around to head back. Just before I got to my exit I noticed the outside temp had gone up to 61 so I drove on by my exit hoping it would keep climbing thinking this may be the computer getting systems adjusted. Seems that was the case. By the time I got to the next exit it was reading real outside air temp. I turned around and headed back. I touched nothing until I got back home. Adjusted my AC and cranked it. SUCCESS!. I've since been out and made some stops. Everything is normal except engine hours. I read that this is a common problem and those won't come back so now my truck with over 140,000 shows that it has only run for a bit over an hour. Who cares! Got my truck back to normal otherwise.
 

winger870

New member
I have a 2005 Sierra 1500 the lower hose clamp that GM uses are the shits they rot out. Mine broke also luckily I never lost any fluid . My friend has a 2013 Sierra the lower clamp let go and he lost fluid and had to be towed. Anyone who has not it maybe a good idea to change the lower rad hose clamp to a good stainless steel gear clamp so you don't end up with an issue when you least expect it.
 
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