HELP!!! I did some welding on my truck and now my check engine light has turned off!!!

So, long story short, I was crawling around under my truck like any normal person does, and noticed a cross member had some cracks in it. So, I actually disconnected the battery this time, and proceeded to weld the cracks back up. While I was down there I tried welding a nut onto a bolt that was broken off on the body to try to extract it. I even moved the ground clamp to a body ground, instead of leaving it on the frame.
Well, this morning I go to start my 900 mile drive and noticed the light wasn't on any more! I even plugged in the obd scanner to confirm what I was (not) seeing, and sure enough, no codes (minus 1 inactive code, something about a maf sensor. No biggie.)

Help! That light has been a guiding beacon for me and now I am mortally lost!

 

Friday always brings powerful posts!

Enjoy the long drive without that beacon flashing at you!

 

Just leave your gas cap loose and you’ll be back to your happy place in no time.

 

Here's what you you do... get some scotch tape! The cheap dollar store shit, none of that good stuff! Run by kinkos and have them print this...



Get a really small par of skizzors and cut it out, apply it to said cheap ass tape and slap the mofo right back on! You'll be good to go! Pro tip, have them print extra in case you lose it.

 

Disconnecting that battery really did you some good lol

 

Copy the gas cap trick! I will give it a go.

Luckily I still have the airbag light, low tire pressure light. And abs/ebrake lights still on. So I am not completely lost yet

 

Thats a good question... kind of odd for my tyranny brace to be cracked in 3 spots. Might have something to do with the assortment of dents on all of the under belly metal parts.

 

Had to repair this one. Plated it.

Crazy yellow light went away too. Might be more than a coincidence......

 

Leaving the battery disconnected for to long can reset the sensors and code history, drive it enough and I'm sure it will come back on.

 

400 miles down and still no light. Might just have to sell the truck now

 

thats amazing haha

 

I think we are on to something! I am going to start recommending this fix to anyone with the magic light on

 

just unplug the map sensor

 

Brilliant

 

You need to polarize the gauge cluster again to get it come back on, when you disconnected the battery the cluster lost its EEPROM memory. To do that simply hook the red to the black with jumper cables and that light will come back on without issue. It's all written clear as day in the back page on the FSM.

 

Clock spring died. I have a new one on order. That will fix the airbag light. And the abs is a pinched wire. I am not a fan of the abs on these trucks any ways. They are a bit too over reactive, and I have had it send me into a bad spot too many times.

 

Ah, what a sign of relief! Crisis averted.

 

Quick. Weld something else!