1227747 to 16197427 Conversion PCM Swap with Wiring Pinout Directions!

[93V8S10]

Got the new book in today, and F8 is the correct pin for the power steering switch. Also, fount out that B1 is for the DIS system used with the 2.2L. It is called the 1X Signal, and is used for ASDF (Alternate Synchronous Double Fire).

Anyone ever find the VATS pin? I'll trade you the AC High Pressure Switch pin. This was used to raise the idle if the A/C pressure got too high (no bins that I know of with this active).

[gregs78cam]

Sounds like that book has some good info in it. It there anything in there that could make sense of this trans datastream portion of the hac?

L53F3    FDB $0010      ; 11,  MALFFLG6, ERROR WD 6
                    ;
                    ; b7 1 = ERR 57. (not used)
                    ; b6 1 = ERR 58, XMISH TEMP HI
                    ; b5 1 = ERR 59, XMISH TEMP LOW
                    ; b4 1 = ERR 61, TURBO BOOST SENSOR HI
                    ;
                    ; b3 1 = ERR 62, TURBO BOOST SENSOR LOW
                    ; b2 1 = ERR 63, BARO SENSOR HI
                    ; b1 1 = ERR 64, BARO SENSOR LOW
                    ; b0 1 = ERR 65. (not used)
                    ;-----------------------------
L53F5    FDB $001B      ; 12, CURMALF5, CURRENT ERROR WD 6
                    ;
                    ; b7 1 = ERR 57. (not used)
                    ; b6 1 = ERR 58, XMISH TEMP HI
                    ; b5 1 = ERR 59, XMISH TEMP LOW
                    ; b4 1 = ERR 61, TURBO BOOST SENSOR HI
                    ;
                    ; b3 1 = ERR 62, TURBO BOOST SENSOR LOW
                    ; b2 1 = ERR 63, BARO SENSOR HI
                    ; b1 1 = ERR 64, BARO SENSOR LOW
                    ; b0 1 = ERR 65. (not used)
                    ;-----------------------------

I was thinking it might be something used in the diesel engine TCM.

Can you shed any more info on any unlisted I/O pins?

[93V8S10]

Nothing about diesel engines, the new book is the S/T Driveability & Emissions Manual. I've woundered about those too.

Here's what I've got so far:

[EagleMark]

Looks like that transmission code was also used in a diesel application. Im my LT1 it is simalar to these PCM that it has engine data and transmission data although I have them in same adx, need to change connection and montitor. Transmission data also shows some engine data and all error codes.

[EagleMark]

Also, found out that B1 is for the DIS system used with the 2.2L. It is called the 1X Signal, and is used for ASDF (Alternate Synchronous Double Fire).

So when is the DIS hac coming out for V8?

[JeepsAndGuns]

So when is the DIS hac coming out for V8?

I havent forgotten or abandoned the northstar DIS we talked about a couple months ago. Once I get my MPFI installed and tuned, DIS comes next.
So I'm intrested in DIS info too.

[93V8S10]

So when is the DIS hac coming out for V8?

LOL, way over my head.


A13 is the A/C high Pressure Switch
E7 is AIR Bypass Control
I'm still uncertain about whether B7 can be used for the underhood ESC.

I'd bet on B11 or B14 being VATS.

[one92rs]

now the vats deal would be cool. since i have it in a 92 camaro it would be cool to have it wired up as well.

[Scorp1us]

We should update the GIF on the front page to t he revised version found here: http://www.thirdgen.org/techboard/po...82-post40.html

Notably, the P/N switch is updated. I've been beating my head against a wall because my IAC isn't working right. Because I don't have the wire hooked up, because it was not on the sheet. It was not grounded so it thought it was in drive and would not do the pintle thing.

[EagleMark]

Thank you and done!

[1project2many]

I have checked the pinout on the first page and cross checked factory pinouts from C/K and S/T vehicles using the same PCM family with manual transmissions. I see no park/neutral switch input or grounded signal wire listed in the OEM diagrams. Also, the two factory diagrams I have show both VSS and trans speed signals connected to the pcm in manual trans applications.

Does anyone have confirmation of P/N input on E5, or of the results of not including the VSS / trans speed signal on F13?
Thanks

[1project2many]

Very interesting that GM found ASDF to produce cleaner emissions in the S10. In some masks ASDF is a function of IPW to prevent commanded on times less than injector is capable of and is implemented without 1X signal. In these cases ASDF is not implemented during most operating conditions. It's noteworthy that GM resorted to hardware solution in 7427. I'd love to have more time to investigate the hardware relationship between the 1X input pin, memcal configuration, and limp mode fueling.

The list of unused pins has been pretty consistent in all of the models I've looked at. A11,A13, B6,B7, B11, B14, E7, F4,F5. Checking multpile vehicles to see if this list can be shortened might be a worthwhile approach.

[TheApocalyptican]

I am planning on switching from the 7747 to the 7427. Need to the get the PCM itself tho, and since I have a V8, do I need a 7427 from a V8, or will the V6 version work too?

[dave w]

I am planning on switching from the 7747 to the 7427. Need to the get the PCM itself tho, and since I have a V8, do I need a 7427 from a V8, or will the V6 version work too?

I've never tried using a V6 Memcal for a V8 engine. I've done several '7427 conversions, all V8 engines and all had V8 Memcals.

dave w

[dumb_dog]

For those interested I have both the DRAC and VSSB. These little boxes convert a 40 pulse tone ring into the signal to for the PCM or ECM, and speedo. The VSSB has more outputs than the DRAC. Power, ground, and sensor inputs are the same. The PCM 427 with VSSB uses the RWAL singal (anti-lock brake signal), 40 PPR signal, and 2000 PPM signal. The VSSB also converts the 40 pulse tone ring signal to 2000 PPM for the Speedo. The DRAC is missing the 2000 PPM signal to PCM but because i am using a cable driven speedo i can use the 2000 PPM signal from the DRAC as the signal into the PCM by relocating one wire. With the correct diagrams and much research they can be used interchangebly.

As a side note from another question long ago in this thread the VATS pin is pin B7. There is no wire in that location but it is +5 volts and when pulled low at 30Hz the PCM will allow engine start. So enable VATS and use pin B7. I have tested it and activtly using it in my conversion.