Shift Light Logic - reprogram to do what I want?

[jmgtp]

As pertaining to the factory shift light in my GP. For those that don't have it, it is basically a little arrow near the tachometer that illuminates when the ecm determines you would be getting better mpg by being in the next gear up (5spd).

I never pay any attention to is whatsoever and have no need for it... however I am wondering if the ecm logic can be changed so I can use the output from the ecm to energize a relay under certain conditions. For example, if i wanted to energize a relay only under full throttle, or only above a certain rpm, can the shift light logic be altered so the ecm would turn the light on under my specified conditions? Obviously, I would just use the output from the ecm intended for the shift light to go to my relay.

The reason I'm asking:
I'm considering an electric vacuum pump, but they are short lived under continued use. I want to be able to have it turn on about 4k rpm or any time the car is about 70% or so throttle. I want to use the shiftlight output to accomplish this. I got to thinking about the shift light and it is essentially a pin out from the ecm that the programming determines when to ground (or power - I don't know which yet). So basically, can my memcal be reprogrammed to meet my needs?

I have the ability to burn my own chips and can make simple changes in tunerpro and effectively burn them. For something this complicated I don't know where to begin. It isn't in the TunerPro definition I have which means either hex editing or it needs to be added. I'm lost on how to do this.

Is this feasible? Can anyone assist in making these parameters available in the TunerPro definition so I can modify and burn all through TunerPro?

[bszopi]

Almost all ECM switching is via grounding the pin, so what you are attempting should be relatively easy on the wiring side. As far as programming, I have no idea...

[Mars]

See, the people that know how to do this kind of stuff aren't talking cause they want to make money off it instead of helping.

I have no idea how you'd ever get that to work myself.

[bszopi]

This is from the 94-95 (2E) DOHC code, but it will give you an idea of what is generally available in the programming as far as the shift light...

;-------------------------------
; SHIFT LIGHT PARAMETERS
;-------------------------------
9796 0x00 ;FMPH – VEH SPD THRESH FOR P/N
9797 0x00,0x00 ;N/V RATIO INDICATING 5TH GEAR HIGH VALUE
9799 0x00,0x00 ;N/V RATIO INDICATING 5TH GEAR LOW VALUE
979B 0x00,0x00 ;N/V RATIO INDICATING 4TH GEAR HIGH VALUE
979D 0x00,0x00 ;N/V RATIO INDICATING 4TH GEAR LOW VALUE
979F 0x00,0x00 ;N/V RATIO INDICATING 3RD GEAR HIGH VALUE
97A1 0x00,0x00 ;N/V RATIO INDICATING 3RD GEAR LOW VALUE
97A3 0x00,0x00 ;N/V RATIO INDICATING 2ND GEAR HIGH VALUE
97A5 0x00,0x00 ;N/V RATIO INDICATING 2ND GEAR LOW VALUE
97A7 0x00 ;MAXIMUM SHIFT LITE ON TIME
97A8 0x00 ;TURN OFF E-LITE IF NEG D-TPS > THIS
97A9 0x00 ;COOLANT THRESHOLD FOR E-LITE ENABLE
97AA 0x00 ;HYST FOR MINIMUM TPS FOR SHFT LITE ON
97AB 0x00 ;RPM HYST FOR MIN RPM FOR SHIFT LITE ON
97AC 0x00 ;RPM ABOVE WHICH LIGHT IS ALWAYS ON
97AD 0x00 ;FMPH
97AE 0x00 ;%TPS
F47G1ST VS RPM/25
97AF 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
97BA 0x00 ;MINIMUM RPM FOR LIGHT ON, 1ST GEAR
97BB 0x00 ;MINIMUM TPS FOR LIGHT ON, 1ST GEAR
97BC 0x00 ;LIGHT ON DELAY TIME, 1ST GEAR
97BD 0x00 ;TPS HYSTERESIS FOR LIGHT ON, 1ST GEAR
97BE 0x00 ;LIGHT ON DELAY TIME, 1ST GEAR
F47G2ND VS RPM/25
97BF 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
97CA 0x00 ;MINIMUM RPM FOR LIGHT ON, 2ND GEAR
97CB 0x00 ;MINIMUM TPS FOR LIGHT ON, 2ND GEAR
97CC 0x00 ;LIGHT ON DELAY TIME, 2ND GEAR
97CD 0x00 ;TPS HYSTERESIS FOR LIGHT ON, 2ND GEAR
97CE 0x00 ;LIGHT ON DELAY TIME, 2ND GEAR
F47G3RD VS RPM/25
97CF 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
97DA 0x00 ;MINIMUM RPM FOR LIGHT ON, 3RD GEAR
97DB 0x00 ;MINIMUM TPS FOR LIGHT ON, 3RD GEAR
97DC 0x00 ;LIGHT ON DELAY TIME, 3RD GEAR
97DD 0x00 ;TPS HYSTERESIS FOR LIGHT ON, 3RD GEAR
97DE 0x00 ;LIGHT ON DELAY TIME, 3RD GEAR
F47G4TH VS RPM/25
97DF 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
97EA 0x00 ;MINIMUM RPM FOR LIGHT ON, 4TH GEAR
97EB 0x00 ;MINIMUM TPS FOR LIGHT ON, 4TH GEAR
97EC 0x00 ;LIGHT ON DELAY TIME, 4TH GEAR
97ED 0x00 ;TPS HYSTERESIS FOR LIGHT ON, 4TH GEAR
97EE 0x00 ;LIGHT ON DELAY TIME, 4TH GEAR
E-LITE TPS THRESHOLD MULTIPLIER VS FILTERED MASS AIR THIS REF
97EF 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
;
;---------------------------------

And this was pulled from http://60degreev6.com/forum/local_links.php?catid=8

[jmgtp]

Thanks, that does help some and give me some hope. Odd to see it in the 94-95 code as those years didnt have the 5speed or need for the shift light, unless it was just leftover from the older code.

It looks like the values are all there to make this happen, I just don't understand the hex stuff at all. I'd need it in TunerPro with values I could adjust, like TPS, RPM etc for it to make sense to me.

I don't understand how to add things to TunerPro. Ben added IAC counts for A/C to my definition. I had a stalling issue with the A/C on and he was able to add this in so I could adjust how many counts the ecm throws at the IAC when the A/C kicked on. I just have no idea how he did it! I have the word document that breaks down the 3.4 code that I have. I could probably locate the shift light logic in there but I just don't know how to get it into TunerPro so I guess that is what I really need help with.

Thanks again and I hope I can keep this thread rolling as I want to learn how to add things to TunerPro (I really need a how to) and see this come to fruition.

John

[jmgtp]

Some Success!

I've made some progress and have entered the constants into TunerPro for the Minimum RPM and Minimum TPS parameters. I've only done it for the 1st gear logic so far, but once I get that all figured out the rest should be cake!

There are a few more things to get this figured out, but at least I've made some sense of the hex code and figured out how to import the logic into TunerPro. Everything I say next pertains to the screen image below which shows the bit of the code I'm looking at on the left and what I've accomplished in TunerPro on the right. One is the window of operation (E6 and E7). The formula is simple at RPM/MPH. I just need to figure out what values I would want to use to make the window very big, so that whenever I go to WOT it is in the window.

The next issue, I'm struggling with. Lines DC through E5 have what I think are TPS % values corresponding to certain RPMs listed on the right side. I'm not sure what to make of this just yet.

There is also some other parameters I need to take into account, like the maximum shift light on time which is currently 8 seconds.

There is also these 2 lines which caught my interest:
00D8 E0 224 KRPMAX 5600 RPM RPM ABOVE WHICH LIGHT IS ALWAYS TURNED ON
00D9 0003 3 KSHFMPHL 0.01 MPH MPH BELOW WHICH LIGHT IS ALWAYS TURNED OFF

if I can lower the first one to 4000 rpm and have the shift light come on and stay on that would be great.