NOTE: This is a work in progress. When I'm done, this will be a how-to thread for making an ABS ON/OFF toggle switch for non-e-locker 96-00 T4Rs.

To Operate:
- ABS OFF: click the toggle down
- ABS ON: click the toggle up (or start the vehicle)

Attributes of this method:
- Uses one switch
- On-the-fly control
- Defaults to ABS ON on vehicle startup
- No new wires through the firewall
- Preserves speedometer functionality
- Original factory dash warning light reports ABS status

@steezemcqueen figured this out originally, but with 2 switches and passing wires through the firewall: ABS disable V2.0 for older 3rd gens (On/off on the fly).

You'll need:
1. One "DPDT (on)-on-(on)" Toggle Switch (e.g. ALCOSWITCH A215SYZQ04)
2. Wire* (one color for the ABS ECU power supply, ideally Yellow)
3. Wire* (a different color for the signal between ABS ECU and ABS Actuator, ideally Gray-Red)
4. more to come...

*Wires need to be long enough to reach comfortably from the ABS ECU behind the passenger kick panel to wherever you plan on mounting the switch.

Background:
When you interrupt the Signal between the ABS ECU and ABS Actuator, the system reports an ABS fault, deactivates ABS, and illuminates the ABS dash warning light. In this state, ABS is OFF. ABS will stay deactivated (OFF) even if you reconnect the Signal between the ABS ECU and ABS Actuator.

When you disconnect the Power to the ABS ECU, the system deactivates ABS, illuminates the ABS dash warning light, but also deactivates the speedometer. In this state, ABS is OFF but the speedometer doesn't work. However, once you reconnect the Power to the ABS ECU, the system recovers, ABS is back ON, the ABS dash warning light turns off, and the speedometer works again. This is what happens when you restart your vehicle.

Overview:
1. To turn ABS OFF (and illuminate the ABS dash warning light), we will temporarily interrupt the Signal between the ABS ECU and ABS Actuator (with a switch). See wiring diagram, gray/red wire, GR-R (A16) between the ABS ECU and ABS Actuator.
2. To turn ABS ON (and turn off the ABS dash warning light), we need to make sure the Signal is connected, and then temporarily interrupt the Power to the ABS ECU (with either a vehicle restart, or a switch). See wiring diagram, yellow wire, Y (B10?) to the ABS ECU.

That's it. We'll use a DPDT (on)-on-(on) switch. It's a three-way toggle switch, where the Up and Down positions both spring back to the Center position. See Switch wiring diagram with descriptions.

With this method you simply click the toggle Down to disable ABS and click the toggle Up to enable ABS.

Since the toggle always springs back to the Center position, it's no problem if you forget to turn the ABS back on after riding a trail: every time you start your truck, ABS defaults to ON and is working normally.

NOTE: I'll add photos and a step-by-step how-to when I'm done...

Big thanks to @steezemcqueen , @Nelsonmd , @88toy4x4 , and others for laying the groundwork.

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