2000 Chevrolet Tahoe LSA Swap - GM 12200411 PCM Implementation
The implementation of the popular Gen III LS-Series 12200411 PCM may seem a little confusing and/or unnecessary. It has no chance of controlling a 58x/4x crank/cam signal equipped Gen IV LS-Series engine, so why would I add this to the project? Let me explain...
The 2000 model year "Black Box" Vortec Vehicle Control Module, or VCM, was originally used for the following vehicle functions:
- EVAP System
- Air Conditioning System
- Fuel Level Gauge (in the Instrument Cluster)
...and has ties to:
- Electronic Brake Control Module (or EBCM)
- 4 Wheel Drive System
The LSA engine requires the use of the E67 ECM. Well, the E38 could be used, but that's not within the scope of this project. The E67 ECM is original equipment for the 2012 Camaro ZL1's LSA engine, so I chose to use it. Once the original VCM is removed from the vehicle, I lose the functions of everything it had controlled. The E67 ECM will take care of the engine management system and EVAP functions for the venting of the gas tank. The T42 TCM will communicate with the E67 ECM for proper 4L80E transmission control. That leaves several important vehicle functions that require additional attention.
While it seems I could keep the original VCM in the vehicle to take care of the remaining systems (Air Conditioning, Fuel Level Gauge, and EBCM), the original VCM requires 4x/1x crank/cam signals to be aware of engine operation. The LSA engine is fitted with 58x/4x crank/cam signals. I'm well aware that GMT400 enthusiasts have been upgrading their 1996-2000 full size trucks to the popular GM 12200411 PCM for greater tuning capabilities (and to work around a pesky 5800 RPM limit). The 12200411 PCM was used in many full size GM vehicles from 2001-2002. It supports 4x/1x crank/cam signals for single coil and distributor ignition and 24x/1x crank/cam signals for coil per cylinder ignition. GMT400 enthusiasts have been successfully repinning their engine wire harness for 12200411 PCM while maintaining full function of the systems mentioned above.
Lingenfelter Performance Engineering developed a 58x/4x to 24x/1x crank/cam signal interface that has been trusted by enthusiasts for nearly as long as the Gen IV LS-series engines have been available. By installing Lingenfelter's TRG-002 interface module, I can simply tap into the 58x crank and 4x cam signals and output 24x crank and 1x cam signals to the 12200411 PCM. I can then use EFILive or HP Tuners to reprogram the PCM and disable all engine and transmission related trouble codes. The PCM will then be used as a stand-alone controller for the vehicle functions that cannot be performed by the Gen IV E67 ECM.
This Tahoe is ditching the 4 wheel drive transfer case and front differential for all wheel drive replacements, so the transfer case electronics won't be used. In other words, the 12200411 PCM's 4 wheel drive related signals won't be implemented.
Here's a thorough look at my implementation of the 12200411 PCM in the 2000 Chevrolet Tahoe Z71.