Home brew diff lock ECU for air lockers

[landcrshr]

This is great.
I am hoping to use some micro boards to eliminate some of my need for relays.
I have a bunch of relays wired in succession to provide logic for my switches.

I would like to see more details of exactly what your board is doing. You mentioned this is a prototype, are you planning on producing any for sale?

The PDF diagram shows it all, the board is just a place to bring the factory wires easily together. I then added supression diodes accross the solenoids (to prevent potential arcing within the CDL indicator switch.)
I added the timer to flash the RDL lamp because I thought that would be cool too.

No plans for production, don't have the means, for now I'm happy to share.

 

[azTony]

I prefer a separate switch for the compressor. I am also looking to use my Puma for the lockers so a separate switch makes sense for my application.

Since I do not have a PT TC I do not know what the pin 15 to GND does

 

[landcrshr]

Exactamundo

making margaritas with the blender

Wait a miniute....do mean you have a pneumatic blender?

 

[landcrshr]

I prefer a separate switch for the compressor. I am also looking to use my Puma for the lockers so a separate switch makes sense for my application.

Since I do not have a PT TC I do not know what the pin 15 to GND does

Grounding pin 15 would tell a factory ECU that the center is locked, enabling the front and rear (and illuminate the CDL indicator lamp.)
This is the sequence that I wanted to emulate.

 

[LandCruiserPhil]

Grounding pin 15 would tell a factory ECU that the center is locked, enabling the front and rear (and illuminate the CDL indicator lamp.)
This is the sequence that I wanted to emulate.

Correct me if wrong but a couple more diodes and jumpers off you negative side of the F&R solenoid to pins 9 & 10 would accomplish F&R locked dash lights.

 

[landcrshr]

Correct me if wrong but a couple more diodes and jumpers off you negative side of the F&R solenoid to pins 9 & 10 would accomplish F&R locked dash lights.

Do you mean pins 9 & 2? No, that would cause both the F & R lamps to be on whenever the center is locked. I used the pressure switches for feedback to monitor the pneumatics side.
This lets you know the lockers are locked, not just the solenoids activated.

 

[LandCruiserPhil]

Do you mean pins 9 & 2? No, that would cause both the F & R lamps to be on whenever the center is locked. I used the pressure switches for feedback to monitor the pneumatics side.
This lets you know the lockers are locked, not just the solenoids activated.

There is where the diodes come in isolating pins 2 & 9. With separate grounds to the solenoids there would no need for the diodes if you bypass the locker ECU and wiring into the wire that goes to the indicator lamps. Right now you are not using much of it anyway.

Not trying to complicate things just trying to help give you the factory look with air lockers.

 

[landcrshr]

There is where the diodes come in isolating pins 2 & 9. With separate grounds to the solenoids there would no need for the diodes if you bypass the locker ECU and wiring into the wire that goes to the indicator lamps. Right now you are not using much of it anyway.

Not trying to complicate things just trying to help give you the factory look with air lockers.

Unfortunately, it's hard for me to picture what you suggest without a diagram. Right now it is working just as the factory system would, but I do welcome all opinions.

Here are some design points.

The two solenoids are NOT normally grounded. They share a common return line back to the ECU, that is then switched to ground when center is locked. There is a diode in this line to keep the CDL lamp from having a path to ground through the compressor when the center is unlocked.

The other 2 diodes are parallel to the solenoids to suppress voltage spikes (a common practice for the switching of coils.)

I had one design constraint: Toyota provided 6 wires running up front for the front diff, but I had 9 wires, so I combined them into the "Bb1" connector like this:

1) Front solenoid +
2) Rear solenoid / compressor +
3) Rear pressure switch
4) Solenoid common return
5) Front pressure switch
6) Pressure switch ground

There was no room for 2 separate solenoid negative wires.

 

[landcrshr]

This is really nice. If the board becomes production it would be really nice for shops to use to reduce install times.


I'm glad you like it!
What you really need is the other end of the front diff "Bb1" connector. If you had that to create a pre-fab harness up front it would truly be plug-and-play.

 

[LandCruiserPhil]

Unfortunately, it's hard for me to picture what you suggest without a diagram. Right now it is working just as the factory system would, but I do welcome all opinions.

Here are some design points.

The two solenoids are NOT normally grounded. They share a common return line back to the ECU, that is then switched to ground when center is locked. There is a diode in this line to keep the CDL lamp from having a path to ground through the compressor when the center is unlocked.

The other 2 diodes are parallel to the solenoids to suppress voltage spikes (a common practice for the switching of coils.)

I had one design constraint: Toyota provided 6 wires running up front for the front diff, but I had 9 wires, so I combined them into the "Bb1" connector like this:

1) Front solenoid +
2) Rear solenoid / compressor +
3) Rear pressure switch
4) Solenoid common return
5) Front pressure switch
6) Pressure switch ground

There was no room for 2 separate solenoid negative wires.

PM sent

 

[alia176]

Wait a miniute....do mean you have a pneumatic blender?

Why, yes I do. One of the advantages of having a York for OBA