ABS Disable: On-The-Fly (no removing fuses)

For those of us who want to temporarily disable ABS without going under the hood and pulling the 30 Amp fuse (brake sensor circuit) or the bolted in 60 Amp fuse (ABS Actuator motor circuit)...

Here are all the details from my research after spending a good amount of time reading the Wiring Diagrams in the Service Manual for the 2003 Tacoma.

My conclusion: This should work on any 2001-2004 Tacoma that has ABS. No matter what size engine, whether or not you have the TRD electronic diff lock, auto/manual transmission since I am only recommending modifying one input on the ABS Actuator ECU and not any of the other ECUs.


OPTION 1: ON-THE-FLY ABS DISABLE
This is my preferred way.
This option fully disables ABS when you intend, just like it is automatically disabled when the rear diff locker is on (if you have it).

This option will need a SPDT switch. In one position, the wiring is like normal when the truck rolled out of the factory. In the other position, you will ground out Pin 19 on the ABS Actuator ECU.

Why the SPDT switch? If you pull this wire to ground, everything else will also get pulled to ground which will

1. Cause the Diff Lock will light up on the dash even though it's not locked
2. You'll confuse the Rear Diff Lock ECU telling it that the Rear Diff is locked so if you did want to lock/unlock it when ABS is disabled, it would not work)

OPTION 2 FOR ON-THE-FLY ABS "Disable"
This version doesn't fully disable the ABS system, it just prevents it from activating. One signal that goes into the ABS Actuator ECU is a +12 VDC (10-14V) signal that is sent in when you press the brake pedal.

If you wire in a SPST switch to this STOP LIGHT wire (Green with white stripe that goes to pin 10 of the ABS Actuator ECU). When your newly added SPST switch is in a "ON" (circuit closed position), ABS will behave like normal. When the SPST switch is in an "OFF" (circuit open position), the ABS Actuator ECU will never receive the signal that you are using the brakes and will not activate. This will not illuminate the ABS light in the instrument cluster (dash) - this may be your preferred way. I would rather have the light on to remind me that I have disabled ABS.


MORE DETAILS / MY RECOMMENDATIONS
FYI - the ABS Actuator ECU is attached to the ABS Actuator itself. This is under the hood, on the passenger side fender. I wouldn't splice into the wiring here as it is exposed to the elements (water/salt/car wash soap/et al) being under the hood. The blue wire with yellow stripe on Pin #19 on the ABS Actuator ECU runs to connector plug J13 which is inside the vehicle, behind the dash on the passenger side. This is where you'll want to tap in. You can't tap in closer to the Rear Diff. Lock ECU - see point #2 under OPTION 1 above.

I am not sure which pin of the J13 connector is the wire going to the ABS Actuator ECU - you will have to determine this yourself as it's the most important thing to get correct in order for proper behavior as described in Option 1.



Also, Junction Connectors are like so (not a male & female plug):




Read through the wiring diagram of your specific year/model official Toyota Service Manual before attempting this and don't blame me if you mess it up.

 

@Blackdawg - what do you think of this? I am opposed to removing ABS from my truck since I let random people borrow it occasionally and don't want to teach them all the nuances with my truck, so having a way to make it "safer" for the less experienced drivers is ideal.

 

Hi!
I would like to do option 1 on a 4runner 2000 without diff lock. I would need more info on the J-13 connector. I can't find it.

Thanks!

 

Hey Jason,

Can you post the '03 Wiring Diagrams that got you to this proposal? I'd like to compare them to my '00 diagrams and see if I can work it out for my year. I'm happy to post up the mapping if I can achieve it.

 

Do you have ABS in the 2000?!? I didn't know it was an option on the early 1st gens (1995-2000).

I'll send you an email with what I have. That content can't be posted on here.