2013 4.3L Intermittent Trans and Engine overheating warning when not overheating

[richard wysong]

Wiring diagram and a DVOM meter, Invest in a factory service manual instead of parts that may not be needed, Haynes manuals are useless, way too generic. Look on EBay

[newdude]

1 hour ago, RadoRevival said:

 

https://g.oempartsonline.com/oem-parts/gm-automatic-transmission-gear-position-sensor-19181161

 

That's where I shopped for the part and it told me it would not fit.

 

Do you have any spot for a tutorial how to change the part out? Do i need to drop the valve body?

 

 

 

The downfall of those "wholesale GM dealer ran" websites.

 

I put a VIN of a 2013 with 4L60 and came up with the first # I posted, 24248867 - Parts (gmparts.com).  This is why the dealer parts counter always ask for a VIN so they can make sure parts fit your truck.   

 

 

But yea, to go back on Richard, time for some diag work.  Scan for any other codes besides the P0128, circuit testing, etc.  Scanning for codes would be the best place to start if you have yet to do so.  

 

If the P0128 is the only code you've got though, gotta solve that first and it might solve your overheat message too (possibly).  

Edited April 26, 2024 by newdude

[RadoRevival]

5 minutes ago, newdude said:

 

 

 

The downfall of those "wholesale GM dealer ran" websites.

 

I put a VIN of a 2013 with 4L60 and came up with the first # I posted, 24248867 - Parts (gmparts.com).  This is why the dealer parts counter always ask for a VIN so they can make sure parts fit your truck.   

 

 

But yea, to go back on Richard, time for some diag work.  Scan for any other codes besides the P0128, circuit testing, etc.  Scanning for codes would be the best place to start if you have yet to do so.  

 

If the P0128 is the only code you've got though, gotta solve that first and it might solve your overheat message too (possibly).  

 

Yeah that's the only code, and I bought both the thermostat and the temperature sending unit. Wasn't sure if I needed one or the other and I figured I'd just change them both. 

Watching my trans temp on my ride home today, it was actually working. Then when I would hit the gas at times it would jump to 250 and instantly back down the normal temperature. 

I ordered a repair manual from eBay, not sure if the quality I will see when it gets emailed to me.

[RadoRevival]

Got my truck on the ramps. The plug is on the top side of the tranny. I dare not pull it out for fear of never getting it back in. I figured that it is the yellow & tan/black wires. I did find them on the transmission control module (pictured below). No idea what I would test or how but quick question, do these wires look like someone has been in here before?

 

tan and black wires. Maybe this has been a problem? What do the tranny gurus think?

 

 

[RadoRevival]

Well, I changed out the thermostat and the temp sending unit today. The retaining clip snapped on the sending unit connector so I get to order a new one and solder that in. What's weird is the OEM is 198° and I think the old one was 185°. So now the temp gauge is straight up and down where it used to be at about 11:00. 

 

But now, I discovered that when the electric fan kicks on the trans temp warning sounds, which is gonna be pretty freaking annoying as summer approaches south Florida. 

[RadoRevival]

Got the new sending unit connector soldered in. Still having the trans temp issue.

[swathdiver]

The factory thermostat begins to open at 187 and is fully open at 195.

 

I think you have a wiring issue, critters may have chewed on your wires.  

[RadoRevival]

7 hours ago, swathdiver said:

The factory thermostat begins to open at 187 and is fully open at 195.

 

I think you have a wiring issue, critters may have chewed on your wires.  

 

 

I guess that's possible but the parts of the wire I can see look fine. 

[swathdiver]

22 hours ago, RadoRevival said:

 

 

I guess that's possible but the parts of the wire I can see look fine. 

4-speed transmission right?  If you look through Precision Transmission's youtube channel, you'll see lots of teardown videos.  Consider watching them to see where the transmission thermometer is located and see if that is something you can change yourself.  Pretty sure it's on the valve body under the pan.  I'm surprised you are not getting codes for it.

 

Has the engine coolant thermostat code come back?

[RadoRevival]

2 hours ago, swathdiver said:

4-speed transmission right?  If you look through Precision Transmission's youtube channel, you'll see lots of teardown videos.  Consider watching them to see where the transmission thermometer is located and see if that is something you can change yourself.  Pretty sure it's on the valve body under the pan.  I'm surprised you are not getting codes for it.

 

Has the engine coolant thermostat code come back?

 

Engine temp fine. 

 

On the 2013 the sensor isnt on the valve body. This has taken lots research. The debate has been valve body, selector, and harness. Pretty sure it's on the harness. GM 24298349

 

 

Edited May 9, 2024 by RadoRevival

[swathdiver]

On 5/9/2024 at 11:07 AM, RadoRevival said:

 

Engine temp fine. 

 

On the 2013 the sensor isnt on the valve body. This has taken lots research. The debate has been valve body, selector, and harness. Pretty sure it's on the harness. GM 24298349

 

 

Yes it is.  You can also get a subscription to AllDataDIY for information on how to properly troubleshoot but if going through all the work to pull the pan, I would just swap the harness.

[Dave Y -]

OP SAID:  I got the high temp AC turned off warning. It started right when I started the engine. Didn't even get a chance to warm up. 

 

I have had the same, exact experience with my 2013 Silverado 1500 WT 5.3L V8.  Temp gauge has stopped working.  Engine, even with continued running/driving, does NOT overheat.

 

How do I clear the warning?  It has been suggested elsewhere that I leave the battery disconnected for an hour to clear the warning.

[RadoRevival]

I have a code reader that clears them out. I think disconnecting the battery will do the same. My code reader was a super cheap one from Amazon. But I replaced the thermostat and the temperature sending unit. I don't know which one it was, but I figured for about 40 bucks for the two it was worth swapping them out. 

 

The only problem I had was the connector to the sending unit broken half when I disconnected it so I had to solder a new one of those in. Since then no problems.

[swathdiver]

On 5/20/2024 at 2:41 PM, RadoRevival said:

I have a code reader that clears them out. I think disconnecting the battery will do the same. My code reader was a super cheap one from Amazon. But I replaced the thermostat and the temperature sending unit. I don't know which one it was, but I figured for about 40 bucks for the two it was worth swapping them out. 

 

The only problem I had was the connector to the sending unit broken half when I disconnected it so I had to solder a new one of those in. Since then no problems.

What's the latest on this?

[RadoRevival]

1 hour ago, swathdiver said:

What's the latest on this?

The thermostat and temp sending unit fixed the engine overhead issue. My trans temp just reads as dashes now which is fine. I go over how I fixed the temp issue here. 

 

https://youtu.be/1BgurxElTYM