pcmhacking.net

Keep in mind you are using a test build, p04 is technically not yet supported. I dont want rumours to start that pcmhammer has problems with p04, before it even supports p04.

Well to clarify for others, I was told to only bench flash P04s with pcmhammer. I’m NOT following those directions.

Here's a hack that may or may not be useful. Instead of a hard code based switch to allow BCM to control fan turn on points or not, I've had it allow BCM to control fans when in normal mode and to lower to the PCM control temps when in performance mode.
Might allow for .000000003% fuel mileage increase.
12588500 as always: This is for FAN 1. All you do is copy it to the fan 2 location to do the same there. (4C350)

At some point I do plan on using actual values for normal mode instead of BCM control, but this was so easy to do it allows me to see how it is in the real world. I do think the 40 degree (F) difference in temps is too big and I'll want instead of the BCM values of 230f maybe closer to 200f.

This setup also allows for always on fans in performance mode if so desired.

I think it is time to find the performance switch pin. I will dig for some schematics.

kur4o wrote:I think it is time to find the performance switch pin. I will dig for some schematics.

FFFFFD17 I believe is the 'MUX' read pin.
Just need to set the correct channel when reading it.

Maybe trace where it get saved and monitor that value.

Found some 2nd gear switch that use the same logic as 4Low/tow and performance switches. Might give you good starting point to figure all the inputs, tracing the board.

It is from 2002 v6 firebird pcm

kur4o wrote:Maybe trace where it get saved and monitor that value.

Found some 2nd gear switch that use the same logic as 4Low/tow and performance switches. Might give you good starting point to figure all the inputs, tracing the board.

It is from 2002 v6 firebird pcm

FFFFFDxx is the address range for the ad in/out.

I mean when pcm read MUX it saves it somewhere as software register. Trace that software register, That manipulate different pins and monitor the software register. Usually you need to apply ground to some of it.

I got you. I followed that software register. There’s nothing else with that pin I don’t think. I’ll double check. I’ll look around for any pins that do weird trans options.

kur4o wrote:Maybe trace where it get saved and monitor that value.

Found some 2nd gear switch that use the same logic as 4Low/tow and performance switches. Might give you good starting point to figure all the inputs, tracing the board.

It is from 2002 v6 firebird pcm

C2 pin21 is the same pin used for the performance shift switch in a 2000 Grand Prix
Here's a presumably stock bin I have from a GTP, it appears to have the performance switch enabled if it's worth taking a look at one where it's actually used. I would recommend only using this for reference and don't attempt flashing it with PCM Hammer, I think this one has blank parameter segment. kur40, what do you use for schematics? the Techline VM I use doesn't show the vehicle info at the bottom like yours, and that seems really convenient in yours.