TrplBlk01

I have been told 3 differant time frames.
Anyone else have a opinion?

STL94LT1

15/20 minutes. Also, turning on the headlights will speed up the process.

TrplBlk01

How does having the headlights on help?

86VetteBill

I think someone is pulling your leg...15 - 20 minutes and turn on the headlights? :rolleyes:

There's an orange single wire atached to the positive cable AT the battery. Mine wasn't the easiest to find. It's a real tight fit, but if you can find it and disconnect it, leave it disconnected for 30 seconds. The nice thing about this method over the "disconnect the negative cable" method is that you don't have to reprogram your radio!

If you can't find it, then do the negative cable - again for about 30 seconds.

DragMan

vader86

it shouldnt take any more than a minute for any current to be out of the system

Bgreenard

I agree, it only take a few minutes. the headlight thing is a good one!

BG

STL94LT1

Hey guys, he asked for opinions, not scientific fact.

I know it is not a GM product, but when I bought a computer chip for my truck from a highly respected Ford tuner. He told me to disconnect the negative battery terminal for 20 minutes and turn the lights on before installing the chip. He said by turning on the lights it would drain any current in the system.

65Z01

My reference, "Chevy Fuel Injection" by Ben Watson, says to remove battery voltage to the ECM ( by whatever method you chose) for 30 sec to reset the codes.

If it causes the ECM to lose stored codes it will also lose all learned presets as they are all stored in RAM with needs power to retain data.

That's my story, and I'm stinking to it! :D

Lone Ranger

The headlights bit would be a way to insure you discharged any stored voltage stored by capacitance in the electrical system. Not really a bad idea to insure complete discharge of any and all stored micro voltage in the electrical system. Turning anything on would do it though, radio, ignition key, headlights, brake pedal, etc.

65Z01

Well that might work unless you open that orange wire (my method too) or pull the ECM fuse.

In that case you could touch the orange wire (from the ECM) to ground to discharge any stored charge.

jfb

The only reason to wait for any amount of time is due to the fact that the ECM has large bypass capacitors on the 12 v line and they must discharge to remove any data in storage. Touching the ECM wire to ground (make sure its not the one going to the battery) will discharge those capacitors and reset the computer.