To avoid these ads, REGISTER NOW!

Welding on a vehicle

rtz

Well-known member
Joined
May 27, 2018
Messages
342
Location
Oklahoma City
I need to make some braces for some side steps on a 2016 Ram ProMaster.

Leave the battery plugged in or unplug it to "protect" the computer?
 
To avoid these ads, REGISTER NOW!

paranoid56

Well-known member
Joined
Dec 18, 2008
Messages
1,596
Location
San Diego, Ca
main thing is to keep the ground right next to where you are welding and dont let it travel though anything important.
 

Buckaroo5

Well-known member
Joined
Oct 18, 2012
Messages
824
Location
Central Ohio
Definitely remove the ground from the battery and locate the welding ground as close as possible to the work as already indicated.
 

nadogail

Well-known member
Joined
Jan 23, 2009
Messages
31,961
Location
Coronado, CA
What he said! Welding current has the ability to mess up a lot of things.

Isolate all the current you can from places where you don't want it.
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
Hook where you are welding, dont mess with the battery. Thousands and thousands of new trucks are used as welding platforms every day. I welded on 10,000 cars, trucks, tractors, , a couple planes, trains, motorcycles.
 
Last edited:

dr_clyde

Well-known member
Joined
Jan 7, 2009
Messages
6,446
Location
Holland, MI
This is one of those things where a little common sense is needed. Welding current wants to go from the welding torch to the welding ground clamp. It will take the shortest path to get there.

If that path is through the vehicle's electrical system, unhooking the battery is not going to do squat. There are so many connections on a vehicle chassis to the electrical system that just unhooking the battery will literally do nothing.

It is always good practice to ground as close to the thing you are welding as possible, and if you can remove the component from the car to weld it, do so.

For example, I wouldn't attempt to weld a header on the car with the ground clamp attached to the alternator bracket. I would ground right to the exhaust.

I have welded on tons of cars and trucks, never removed the battery cable, and never had any problems.

I'm not saying welding can't or won't do harm to a vehicle, but unhooking the battery is basically a placebo. If it gives you the warm fuzzies to pop off the ground clamp, go for it, but you would need to also disconnect every other connection the wiring has to the car for this to be effective.
 

txvwnut

Well-known member
Joined
Jan 1, 2015
Messages
7,629
Location
Bedford, Texas
While not a car I had to have a field repair on a Sterling truck with a c-12 Cat engine. The guy that did the weld said you don’t need to unhook the battery. He clipped the ground next to where he was welding and went to work. When done I had to have the ECU replaced as the transient voltage/current wiped out the ECU. I always unhook the battery when welding on a vehicle that has been built in the last two decades.
 

dr_clyde

Well-known member
Joined
Jan 7, 2009
Messages
6,446
Location
Holland, MI
While not a car I had to have a field repair on a Sterling truck with a c-12 Cat engine. The guy that did the weld said you don’t need to unhook the battery. He clipped the ground next to where he was welding and went to work. When done I had to have the ECU replaced as the transient voltage/current wiped out the ECU. I always unhook the battery when welding on a vehicle that has been built in the last two decades.

Yeah, but what good does removing the battery cable do?

I'm sure the welding did the damage, but why would the battery matter? There are lots of other connections between the chassis and the electrical system.

The battery ground connects to the frame, just like every other ground on the truck. Why does disconnecting one of them matter when there are lots more?

If you want to be safe, pull the ECU, not the battery cable.
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
I agree with the dr here, never really had anyone be able to splain how disconnecting the bat ground did anything. Muffler shops weld on hundred thousand cars a day.
Damage to a wire harness would be the most likely issue.
Thousands of cars damaged every day being worked on/equipment disconnected/connected every day, battery explosions are common.
 
Last edited:

DTE

Well-known member
Joined
Jul 13, 2013
Messages
996
Location
North Carolina
A friend of mine runs a shop and they do a lot of exhaust work . They use a surge protector that clamps on the battery terminals.
 

pi_guy

Well-known member
Joined
Jul 27, 2014
Messages
2,818
Location
N/A
As a TIG welder I would disconnect battery and ECU.
The stuff I work on has a battery shut off switch and ECU many as rare a hens teeth are quickly removed.
Back in the 70's I blew the diodes in my glass top stove while tig welding and every time I forgot to turn off the circuit breaker on the stove I blew the diodes.
Had purchased a quantity of them and got pretty good at changing diodes.

So my experience taught me that extra precaution can save my ****. With rare ECU's with custom programming it is not worth the risk to me.
 

dr_clyde

Well-known member
Joined
Jan 7, 2009
Messages
6,446
Location
Holland, MI
TIG welding in particular has the high frequency issue, which can mess with electronics in the area. Doesn't even need to be wired together. My Syncrowave will mess with my employee's bluetooth headset across the room on AC with the HF on continuous.
 

GaryM909

Well-known member
Joined
Apr 11, 2016
Messages
1,528
Location
Calgary, Alberta, Canada
I run a diesel truck with a diesel welder and when working off the back of the truck I have never disconnected the batteries. Always ground close to the work. Never had any problems.
 

Graham08

Well-known member
Joined
Dec 10, 2007
Messages
713
Location
Iron Station, NC
I agree with the "disconnect the ECU" comments, and have done that when welding on vehicles, as well as ground as close as practical to what you're welding. Don't ground to the chassis if you're welding suspension...you'll be surprised what will get smoked in the process if you do.

The other one is to pull the magneto out of a sprint car or similar that use them for ignition. They're very sensitive to welding current.
 

pi_guy

Well-known member
Joined
Jul 27, 2014
Messages
2,818
Location
N/A
TIG welding in particular has the high frequency issue, which can mess with electronics in the area. Doesn't even need to be wired together. My Syncrowave will mess with my employee's bluetooth headset across the room on AC with the HF on continuous.

Radio wave interference generating noise on a wide spectrum.
The house next door used to complain about TV reception going away and he could never understand why. I never bothered to tell him.
Never bother us as it did not effect cable reception, but forget the circuit breaker and dinner was late.

I have found that my newer Dynasty has much less interference with other electronics.

Most of the ECU's in my world travel in anti static bags in padded cases.
 

dr_clyde

Well-known member
Joined
Jan 7, 2009
Messages
6,446
Location
Holland, MI
Radio wave interference generating noise on a wide spectrum.
The house next door used to complain about TV reception going away and he could never understand why. I never bothered to tell him.
Never bother us as it did not effect cable reception, but forget the circuit breaker and dinner was late.

I have found that my newer Dynasty has much less interference with other electronics.

Most of the ECU's in my world travel in anti static bags in padded cases.

Yeah, the Dynasty uses a different high frequency generator, and has a much less profound effect on electronics than the old school transformers do.
 

joe49

Well-known member
Joined
Sep 25, 2009
Messages
1,883
Location
Tonica, Il
Induced voltage is the only worry. Welding does produce this. What is important is not the battery being disconnect. It is not routing welding leads near sensitive electronics or wiring leading to them. I'm in the not disconnecting the battery group and agree with the close/direct grounding of the weld leads.
 
To avoid these ads, REGISTER NOW!

Ign

Well-known member
Joined
Jul 7, 2006
Messages
12,769
Location
Butte Peak ND
Ya know this got me thinking we all know ECU removal can be difficult on a lot of vehicles, so I wonder if an ECM fuse (where applicable) would provide a measure of protection?
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
I run a diesel truck with a diesel welder and when working off the back of the truck I have never disconnected the batteries. Always ground close to the work. Never had any problems.

We got people don't read all that well, you should repeat this. You and thousands of others work off trucks for decades, old trucks and new ones, brandy new hi dollar ones, thousands of them. Don't fuk with ecu. Done this thousands of times,,, figure if it was a problem that at least one of those would have went south?
 

zkdiesel

Well-known member
Joined
Oct 6, 2013
Messages
8,345
Location
chicagoland cornfields
While not a car I had to have a field repair on a Sterling truck with a c-12 Cat engine. The guy that did the weld said you don’t need to unhook the battery. He clipped the ground next to where he was welding and went to work. When done I had to have the ECU replaced as the transient voltage/current wiped out the ECU. I always unhook the battery when welding on a vehicle that has been built in the last two decades.

Cats do that a lot
Odds are it didn’t cook your ecm, it just wipes it out and blanks it. Brought several back from dead by rewriting all the ecm data line by line.

All my customers have a flash file saved In my laptop of the ecm calibration whenever I see a truck that I will work on in future. One comes In on the hook blank, I look up the engine serial number and flash it back in about 10 minutes... if it’s a truck I haven’t see, I get a serial number with same front prefix to burn it, then adjust it for that truck as needed
 
Last edited:

pi_guy

Well-known member
Joined
Jul 27, 2014
Messages
2,818
Location
N/A
Ya know this got me thinking we all know ECU removal can be difficult on a lot of vehicles, so I wonder if an ECM fuse (where applicable) would provide a measure of protection?

With a TIG welder I would go through the process of removing it.

If it was MIG or ARC I would be less concerned but still observant depending on where the welding was.

Been welding stuff since the 70's many times under race track pressure and I am happy with the decisions I have made and the procedures I follow. When your dealing with stuff no longer produced and few of them made caution is a better process than Damm the torpedoes and where is the short cut....
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
This would be true IF there was an advantage. Other wise it's adding to problems,, every welder fooling with fussy cars, want the muffler man tearing in to the ecu and electronics of your car,, or even messing with the battery and under the hood?
 

pi_guy

Well-known member
Joined
Jul 27, 2014
Messages
2,818
Location
N/A
This would be true IF there was an advantage. Other wise it's adding to problems,, every welder fooling with fussy cars, want the muffler man tearing in to the ecu and electronics of your car,, or even messing with the battery and under the hood?

Would not expect any other response from you.
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
I been at this a while. It's been a while since I been to the school but worked on thousands of cars, one of the current, a 14 flex, brakes, transfer case, wheel bearing, the usual and don't even know where the ecu is. I am a pretty careful concienious guy,, amaze myself on occasion with human error,,, it's difficult to imagine the potential damage would,, could be done if everyone unhooked a bunch of sensitive stuff every time they worked on a car, the added cost would be astronomical.
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
Lots of oil changes gone wrong, imagine another million cars a day messed with underhood, complicated connectors, all different wire harnesses. We read about some computer problems on forums because some are brought there and we had some issues early on, it was us more than the cars but I can't even remember the last time I had a problem with something like that and then it wasn't usually the problem.
I was at a buds shop, his helper got half the car apart, I finally had enough, the fukki car starts without the dam thing,, had to twist his arm and have Ricky threaten to fire him to run a comp check, replaced dam near every part on the thing, burnt exhaust valve.
 

pi_guy

Well-known member
Joined
Jul 27, 2014
Messages
2,818
Location
N/A
We work on different things.

In 1985 or 86 I was crew chief for a 944 turbo Porsche one of 6 in country with out AC a show room stock racing version. We were running in ****** Endurance series. I built the roll cage to my specs, following rule book but adding a little more safety. The owner freaked as I ran the bars through the air vents. I won that argument.
We did a few races then a 24 hour race at Nelson Ledges a brutal bumpy track. After race I said the spindles must be tested. The owner said too much money they are fine.
I resigned!

Guess what broke at next race? Well the car dug in and flipped and cartwheeled to a stop. The car was destroyed.
Later on I was running the driver of the car in a formula car. He took me to a bar and thanked me many times for saving his life or from serious injury. He made me promise that I would always follow my design and race car tech methods.

So my view is different and at my age there not many people unhappy with the way I do things there a few people unhappy because I will not do things their way....
 

Ole Slewfoot

Well-known member
Joined
Feb 22, 2016
Messages
5,098
Location
Freedom, CA
If I were going to do something, on a newer car I'd wait a half hour without touching the doors for all the CANBUS stuff to finish
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
We work on different things.

In 1985 or 86 I was crew chief for a 944 turbo Porsche one of 6 in country with out AC a show room stock racing version. We were running in ****** Endurance series. I built the roll cage to my specs, following rule book but adding a little more safety. The owner freaked as I ran the bars through the air vents. I won that argument.
We did a few races then a 24 hour race at Nelson Ledges a brutal bumpy track. After race I said the spindles must be tested. The owner said too much money they are fine.
I resigned!

Guess what broke at next race? Well the car dug in and flipped and cartwheeled to a stop. The car was destroyed.
Later on I was running the driver of the car in a formula car. He took me to a bar and thanked me many times for saving his life or from serious injury. He made me promise that I would always follow my design and race car tech methods.

So my view is different and at my age there not many people unhappy with the way I do things there a few people unhappy because I will not do things their way....
It's great to meet a real hero.
 

bradpac

Well-known member
Joined
Sep 8, 2013
Messages
721
Location
Central TX
How about an argument of keeping the battery hooked up, might actually help absorb some of the noise running through the vehicle while welding on it?

The argument of removing the negative cable while leaving everything else still grounded to the chassis being moot is sound, but I believe batteries absorb a lot of the noise from the electronics that are normally part of the car itself. Maybe it would actually help to keep the batteries connected?
 

Jlarson

Well-known member
Joined
Mar 27, 2015
Messages
738
Location
AZ
Customer equipment yes, and always careful where the ground is. That goes for any time really bearings, bushings, and facility wiring don't like stray welding current either.

I've welded tons and tons of stuff on the tailgate of my service truck and never had a problem with the battery connected, TIG included.
 
To avoid these ads, REGISTER NOW!
Top Bottom