99-01 ECM Transplant in a 97

[freddys]

As far as I know right now I can go from a 1997 1/2ton ECM to a 1997 3/4ton or 1ton ECM without any problems right! What about going from a 1997 1/2ton to a 99-01 HD EMC can you do it without major problem

[diesel65]

Scroll down and read topic "PCM Program" started by Gapper

[freddys]

Diesel65 can you tell me what all you had to do to change it over to the 99-01 HD ECM?

I got a GM Buddy that is going to take a look to see how we can bypass the passlock system without having to change the steering column. I had a GTA before that we bypassed the passlock system on and it was easy. Sure would like to put in a 99-01 HD ECM.

Freddy

[triggerman]

From what I'v read here, there is a good chance you don't have the security item in the 97's. It's the 98's and up. So its still a matter of disabling the newer PCM security codeing.

[diesel65]

I installed a 99 steering column to make the system work, BUT!!!! it is not a plug and play system.
There various other things that are needed in order to make it work, under the AM/FM radio there is a module, in 97 it is called a EVO module but in 98-99 it is called a Passlock/EVO module, also the 97 only has a 10 pin connector the 98-99 has a 16 pin connector.
There are no wires or terminals installed in the main harness to hookup this system, so I had to fabricate a mini harness to tie-in the steering column to the Passlock/EVO module and the security light in the dash cluster.
The 97 module was already wired with the serial data line to the PCM so I didn't need to touch that.
If you could install the correct module and then figure a way to simulate if you were actually inserting a key into the lock cylinder and trying to start the truck I guess you could make the 98-99 PCM work.

[freddys]

I was thinking that the ECM must be looking for a Positive signal or a ground signal right now I am not sure if its + or

[freddys]

Ok was doing a little thinking about a interface Module that is used on a autostart remote car starter this module sends the right signal back to the computer so you don