Pinout and circuit for the G4 Sawtooth switch cable

[minihack]

Hi all,

I've seen a few people ask for this over the years, but had not seen it posted. I was just going to bypass the switch etc. on my mod but looking at it it all looked pretty easy to work out with a multimeter.

Here is the pic of the circuit itself:

stock_board-4983_0.jpg

Top tact switch (S1) of course is the power switch, bottom left (S2) is the reset switch, bottom right is the "programming switch" (S3).

Here is the pinout (so I have got it written down and to help others!).

If you cut the ribbon cable coming from the board and want to wire PC connectors to it, do the following.
cables.jpg

Lay the cable flat with the single red cable on the left. Cables from left to right (or top to bottom on my photo) and with numbering 1 to 10 and with the PC functions marked by me in green are:

1.S3+ programming switch; Don't use.
2. No connection.
3.S2+ Reset switch.Use for reset switch + if you want
4. No connection.
5. S1 +; Use for Power Switch +
6. No connection.
7. Not useful (part of the apple circuit).
8. COMMON GROUND; Use for Power Switch -
9. Anode 1 (glows LED Green); Use for Power LED +
10. Anode 2 (glows yellow); Don't use.



This numbering is also the same as Apple use on the circuit board.

P3110469.JPG

This photo above just shows the connections you will be left with. The blue and white is the power switch connection (Blue = +ve and connects to cable 5 of the ribbon; White = common ground and connect to cable 8 of the ribbon); the green wire (connected to cable 9 of the ribbon) is to go to the + connection on the motherboard for the Power LED to glow green when the PC is on.

The red wire in the picture I connected to cable 10 on the ribbon, just for experimenting but I am NOT using on my board as I don't like the yellow and it does not flicker with HDD activity and just glows sickly yellow. I did not bother with hooking up the reset switch yet as I have no use for it. It does work though and has been tested.

Please note that this board uses a common ground and that is fine - all the functions on an ATX for LEDs and Switchs also have a common earth so as long as wire 8 is actually connected to a ground (best and easiest to use it to connect to the power switch ground) the board will work fine for us without needing to get down and dirty with the circuits. What I mean by this is that the LED and reset switch etc. only need to have their positive side connected at the PC motherboard. There is absolutely no need for cutting of PCB traces for this module to work - it's all fine and good to go with just the simple wiring job detailed above.

Hope this is useful to all and another good resource for G4s!

 

[roto31]

Kick a@@ !!!! Aboout time someone took the time to figure this out It is super appreciated. Looks like I have my weekend project . Now if i could only find the flat ribbon cable from my "Sawtooth" build to complete it. Pictures will be a big help being some of us on here are more visual when it comes to these things. Do you happen to know how the 10 wires are pinned out in the connector ? If so it could be a boost to giving it a more "factory look by snipping those wires and slightly wiring and modifying the other end of the connector.

Again thanks a lot. I propose a thread of "golden threads" for G4 mods starting with the "Sawtooth" on up. It's the basic parts of a G4 mod like this that are missing : for those of us who have done a G4 mod.

 

[minihack]

Kick a@@ !!!! Aboout time someone took the time to figure this out It is super appreciated. Looks like I have my weekend project . Now if i could only find the flat ribbon cable from my "Sawtooth" build to complete it. Pictures will be a big help being some of us on here are more visual when it comes to these things. Do you happen to know how the 10 wires are pinned out in the connector ? If so it could be a boost to giving it a more "factory look by snipping those wires and slightly wiring and modifying the other end of the connector.

Again thanks a lot. I propose a thread of "golden threads" for G4 mods starting with the "Sawtooth" on up. It's the basic parts of a G4 mod like this that are missing : for those of us who have done a G4 mod.

Yep, I have relayed to the connector too - in fact I started at that end. Will post pic.s up v. soon. Just been drilling the standoffs using my template. Thought I'd try it the traditional way first!!!!! Those race track slots can be a bit of a pain, but it's working now......

 

[roto31]

I've actually clipped the end off with the connector to save it for later and twisted the individual connectors on it for the time being to test it out. I followed the what you had wrote down following left to right and it should work. It comes to mind that there was another individual who posted his build on youtube that used a multimeter and traced the circuit path on the actual board and soldered the wires for the positive and negative leads for the power switch, reset switch, and power LED then cut the traces on the board by a good margin so no more current would pass through. It's a different way of dong it but a lot more wok is required though.

Thanks again, looking forward to pics and seeing the process on your sawtooth build. I'm sure it will be as excellent as your other builds

 

[minihack]

Thanks Roto - I have re-done the first post with some extra photos and re-done the numbering to accord with Apples numbering on the circuit board (mine was opposite and I didn't want to confuse!). I corrected one wire relating to the programming switch also.

I recommend using the green LED connection instead of the yellow (just I think green is nicer!).

 

[roto31]

I recommend using the green LED connection instead of the yellow (just I think green is nicer!).[/quote]

That would make the most sense too because green was the original factory standard when it the "Sawtooth" was powered on originally and the amber/yellow light was for when it was sleeping. And it is a success too. No more annoying click though. I just have the power working now, gotta do the essentials first.

 

[minihack]

Hi again - just to let you know (I'm sure you spotted already!) that there were a few typos (hangovers from me changing the way I numbered to accord with the Apple numbering). Main thing I wanted to re-state was that the common ground signal is cable number 8 now that the numbers were reversed. Think I have got rid of any remaining bugs in the first post and glad that this has helped you Roto31.

All the dremeling is done on my Sawtooth case now. Still waiting on some cabling though as the guy on eBay sent me cables that he had meant to send someone else.......

 

[thin_soldier]

This helped me so much! you rock

 

[ace192]

just a note - my circuit board for power is more complicated, it has a chip on the board so i don't have access to power switch, but reset switch works so it'll have to be that one lol... great info!

 

[graphicstation]

Took this a step further, no splicing of wires, no soldering, just used jumper cables, matched them up (based on your pin ID, tsk) to the front panel connector and mobo pins (specific to my mobo) as well as the speaker.