Codes

RP53 · April 24, 2017

don't know where to start, my truck is Chevy Certified" so this should be warranty work. took the truck in because the driver side rear brake was hanging, next thing I know dealer said couldn't replicate, but found a "bulletin for a transmission grinding and they had dropped the transmission pan and checked it out. I though great new transmission fluid for free. but they didn't find anything wrong with the brakes. when I went to pick up the had a tec ride with me for the brake issue I described. made the noise like I had described. he said "it know what that is and we can fix it" it was late in the day and we were going camping so they said it is OK to drive so just drop it Monday AM and we will do the repairs.

well went to campground truck ran fine, I had forgotten something so got in to go to store, Truck wouldn't even turn over, and all kind of codes started popping on the display, Stablink, anit lock braking, transmission issue, power steering limited, and there were more. also the check engine light came on. had to have the truck towed back to dealer, and have father inlaw take the camper home. has anyone else ever had an issue like this ? do you guys think they screwed up my Trans when the "checked it out"

RP53 · April 25, 2017

new developments, talked with the service guys this morning, they told me there were 6 pages of codes they are trying to work through, I know nothing about this stuff is 6 pages a lot ???

2016 Sierra Owner · April 25, 2017

I don't see how checking the transmission would cause the truck not to turn over. It sounds to me like a electrical ground issue by throwing the codes. Hopefully they will get you fixed up fast.

RP53 · April 25, 2017

I would like to hope they wouldn't screw it up but who knows. And yeah I hope they get it fixed fast, thanks for the reply

sk · April 26, 2017

Tell them to check the G218 ground. There is a procedure for this where the ground had some rubber matting stuck between it and wasn't getting good ground. It can cause the BCM to get "confused" and throw all kinds of codes. You can search these forums for it.

RP53 · April 28, 2017

well got the truck back its running fine right now they had 6 pages of code to work through, apparently all were related to low voltage, strange thing is my battery wasn't low had a full charge, it scary part is the said they really don't know why this happened, and it is possible but not likely it could happen again.

sk · May 1, 2017

well got the truck back its running fine right now they had 6 pages of code to work through, apparently all were related to low voltage, strange thing is my battery wasn't low had a full charge, it scary part is the said they really don't know why this happened, and it is possible but not likely it could happen again.

Unfortunately it WILL happen again. What they are saying is true. The battery can have a good charge but something causes the voltage to drop below 12V (usually closer to 9V). When this happens the BCM gets confused and starts throwing pages and pages of codes. The only fix is to find the short, arc, or bad ground that is causing the voltage drop. Here is some info on a couple trouble spots:

http://gm.oemdtc.com/3194/reduced-power-steering-assist-engine-stall-ipc-radio-hvac-goes-blank-various-dtcs-2014-2016-cadillac-chevrolet-gmc

RP53 · May 1, 2017

thanks of that info, can you tell me where the G218 connection as maybe i can look at it myself. you explaining a drop in voltage makes me wonder if i caused it myself. as i had said we were camping and i may (can't remember) have raised my Travel trailer using the electric jack with the engine on the truck turned off while still hooked to the camper, i do know the jack draws a lot of power. do you think that could have happened

Garykk · May 2, 2017

I don't think drawing down the battery will set off the codes you describe. I tow our truck behind a RV and I have killed or close to killed the battery a couple of times until I put a good charge wire in it and never had any codes..

sk · May 2, 2017

thanks of that info, can you tell me where the G218 connection as maybe i can look at it myself. you explaining a drop in voltage makes me wonder if i caused it myself. as i had said we were camping and i may (can't remember) have raised my Travel trailer using the electric jack with the engine on the truck turned off while still hooked to the camper, i do know the jack draws a lot of power. do you think that could have happened

Probably not. Like Garykk said it's not the charge in the battery. It has to do with a short or bad ground making the system lose voltage somewhere between the battery and BCM.

Look at the link I posted. The G218 ground is way up in the front left corner of the dash. You need to remove the pillar trim, then the front cover of the dash near the windshield, then usually the front dash speaker. Then when you look down in the far front corner you can see the ground stud they are talking about. There is a similar one on the passenger side that doesn't seem to be a problem but you might as well check it while you have everything torn apart.

2strokesmoke · May 2, 2017

thanks of that info, can you tell me where the G218 connection as maybe i can look at it myself. you explaining a drop in voltage makes me wonder if i caused it myself. as i had said we were camping and i may (can't remember) have raised my Travel trailer using the electric jack with the engine on the truck turned off while still hooked to the camper, i do know the jack draws a lot of power. do you think that could have happened

Here is where it is located number #1 on image

RP53 · May 2, 2017

Thanks looks like it will be a bear to get to

2strokesmoke · May 3, 2017

The codes set, are a result of low operating voltage, not a low voltage source from battery!

This problem is equivalent to having a underrated or loose negative ground wire to draw from.

This will happen again, and can cause a fire as well....have them recheck that ground nut connection.

Best of luck

RP53 · May 3, 2017

Thanks will have it checked

RP53 · May 10, 2017

The codes set, are a result of low operating voltage, not a low voltage source from battery!

This problem is equivalent to having a underrated or loose negative ground wire to draw from.

This will happen again, and can cause a fire as well....have them recheck that ground nut connection.

Best of luck

amazing, showed the dealer the info you gave me concerning my problems they told me that they could check the 3 points you mentioned, However if they turned out not to be the issue warranty wouldn't cover the labor cost and i sill wouldn't know what the problem was