PCM and Welding
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PCM and Welding
Has anyone experienced a problem with having something welded on your car and it affecting the PCM??
I was reading this on another site about disconnecting the PCM if any welding needs to be done that disconnecting the battery was not sufficient.
Any experiences??
I was reading this on another site about disconnecting the PCM if any welding needs to be done that disconnecting the battery was not sufficient.
Any experiences??
Team Owner
Joined: Jul 1999
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From: Buy USA products! Check the label! Employ Americans
I have a large truck ( no computer) and forgot to disconnect the battery and started to smell plastic. It was the wiring harness 
by the rear tailights. Disconnect it! Not sure if you need to disconnect the computer but you better find out for sure.
by the rear tailights. Disconnect it! Not sure if you need to disconnect the computer but you better find out for sure.
Drifting
Joined: Oct 2004
Posts: 1,384
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From: Southwest Virginia
I just do a LOT of welding and plasma cutting on a Z06 rear with no problems. 
I didn't unhook anything and it still starts and runs fine. I think the key to welding on a vehicle it to make sure your welder ground is attached to what you are welding on and close to where your welding. Don't clamp your welder ground on the vehicle frame when your welding the exhaust. 
Don't clamp your welder ground to the engine when welding on the frame. 
Clamp your ground to what your welding and you shouldn't have any problems. 
I didn't unhook anything and it still starts and runs fine. I think the key to welding on a vehicle it to make sure your welder ground is attached to what you are welding on and close to where your welding. Don't clamp your welder ground on the vehicle frame when your welding the exhaust. Don't clamp your welder ground to the engine when welding on the frame. Clamp your ground to what your welding and you shouldn't have any problems.
Melting Slicks
Joined: May 2003
Posts: 2,851
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From: San Bruno Ca
Originally Posted by SpeedyZ
I just do a LOT of welding and plasma cutting on a Z06 rear with no problems. I didn't unhook anything and it still starts and runs fine. I think the key to welding on a vehicle it to make sure your welder ground is attached to what you are welding on and close to where your welding. Don't clamp your welder ground on the vehicle frame when your welding the exhaust. Don't clamp your welder ground to the engine when welding on the frame. Clamp your ground to what your welding and you shouldn't have any problems.
I didn't unhook anything and it still starts and runs fine. I think the key to welding on a vehicle it to make sure your welder ground is attached to what you are welding on and close to where your welding. Don't clamp your welder ground on the vehicle frame when your welding the exhaust. Don't clamp your welder ground to the engine when welding on the frame. Clamp your ground to what your welding and you shouldn't have any problems. 
I did some MIG welding myself on my exhaust and it has no issues at all
Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
Originally Posted by pewter99
Has anyone experienced a problem with having something welded on your car and it affecting the PCM??
I was reading this on another site about disconnecting the PCM if any welding needs to be done that disconnecting the battery was not sufficient.
Any experiences??
I was reading this on another site about disconnecting the PCM if any welding needs to be done that disconnecting the battery was not sufficient.
Any experiences??
Bill
Melting Slicks
Joined: Jul 2004
Posts: 2,826
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From: Central NJ
St. Jude Donor '05-'06-'08-'10
You should definitely disconnect the battery ground when welding. You shouldn't have to disconnect the actual pcm, but I would wait 30 minutes or so after the battery disconnect to make sure the backup power to the pcm is shut down.
