Digiplex ECU

So, after reading post "308 no spark on 4&8" there was a lot of people helping out a friend, which I find to be great and happy that the problem was found with that said I would like to explain the Digiplex, this is what I know about it, first thing is the controller monitors engine vacuum (engine load), engine speed and depending on model engine temperature, each controller only works one bank and only one controller gives a tach signal to the gauge (bank1 1-4), both controllers share the same power (12v) and ground inputs as well as input from engine speed sensor, if equipped a temperature switch (ground input @ a preset temperature), below I am listing the terminal number, color of wire and what is it used for. The controller takes inputs from the Engine Speed sensor, Engine Vacuum(engine load), and if equipped temperature switch, it only needs to know when to fire the coil but does not know which cylinder is firing that's the job of the distributor and being the advance of spark is controlled by the Digiplex the rotor has a wide face connection to the cap so that the controller can advance or retreated without and mechanical mechanism inside the distributor, being the engine is treated as a 2 4-cylinder engine having 2 banks and 2 controllers each bank working as its own engine, outside of terminals #1 & 5 both controllers share the same inputs and both have terminal #11 as independent coil output. Yes controller #1 does tell the tach engine speed but that can be from either controller if you want it be. as soon as I get some time, I will try to make some videos on how to set up a lab scope with the proper settings and what each sensor should look like on a known good car, I use to different types of scopes one is a SUN LS2000 2 channel and can be found cheap on Ebay this unit will meet any need you will have, and my work scope is a TIE-PIE pc base unit which is over kill for this type of work but will be easier to upload.


Controller #1 bank 1 1-4,

1) Blue to Yellow on 1-4 TDC sensor. (A/C signal input)

2) Shared by both controllers Red/Black to Black on Engine Speed sensor. (A/C signal input)

3) Shared by both controllers Red to Red on Engine Speed sensor. (A/C signal input)

4) Not Used

5) Green to Red on 1-4 TDC sensor and Green at diagnostic connector. (A/C signal)

6) Shared by both controllers Pink/ Black If equipped a temperature switch (ground input @ a preset temperature) comes from switch that will also turn a light on the dash if engine reach's a set temperature, reduces timing, only found on some models.

7) Not Used.

8) Shared by both controller's Yellow Key on power (12volts) from fuse box.

9) Shared by both controller's Black chassis Ground.

10) Only controller 1 for Bank 1 1-4 Brown/Black goes to Tach Gauge. (A/C output Pusle signal for gauge)

11) Coil #1 ground output Green. (D/C output to ground opens when spark event is triggered)


Controller #2 bank 5-8,

1) Black to Black on 5-8 TDC sensor.

2) Shared by both controllers Red/Black to Black on Engine Speed sensor.

3) Shared by both controllers Red to Red on Engine Speed sensor.

4) Not Used

5) Yellow to Yellow on 5-8 TDC sensor and Yellow at diagnostic connector.

6) Shared by both controllers Pink/ Black If equipped a temperature switch (ground input @ a preset temperature) comes from switch that will also turn a light on the dash if engine reach's a set temperature, reduces timing, only found on some models.

7) Not Used.

8) Shared by both controller's Yellow Key on power (12volts) from fuse box.

9) Shared by both controller's Black chassis Ground.

10) Not used.

11) Coil #2 ground output Yellow/Black (D/C output to ground opens when spark event is triggered).

 

85 308QV

Image Unavailable, Please Login

 

thanks this will make it easier to understand,