Hey guys. Doing a 2004 5.3 LM7 swap into a 97 GMC 1500 2wd. Using 4l60e trans with it.

Question I have is related to the trans range switch and the shift indicator in the dash. The 97 used the range switch to directly ground the leds in the cluster for all the gears, real easy. Issue I am seeing with the 5.3 pcm is that it reads the range switch directly. Now heres the rub, from the info I have on Mitchell Ondemand is that the PCM supplies a 12 volt signal to the switch and when it grounds out it knows what gear its in. Seems odd that it wouldnt just read ground but appears that it looks for a short. This is problematic cause I was going to just splice in the shift indicator wiring to the engine harness and feed both the PCM and the dash. If I apply power to both sides of the LED nothing will happen. I do know that I could possibly run the indicators direct and remove it from the PCM but that takes away some of the diagnostic info on the scanner if theres an issue down the road.

Am I mistaking the info I have and I can indeed just splice them together or is something else necessary to do this? Everything else on the swap has been just about plug and play being that they are so similar but this is a sticky point that I want to figure out prior to finallizing the wiring.

Thanks.

 

I just went to house of a friend that we did a 5.3 swap on and I checked to see if there was actually 12 volts on the range switch. The pcm doesnt apply a true 12 volts on the circuits its floating voltage when its unplugged.

This means that I can splice into it just like I expected