Do I Lose ABS When Switching To A Standalone?

[JarrettL]

After looking at the R34 wiring diagrams and seeing that ABS and traction control are combined within the same control unit, I'm wondering what results people who have gone to a standalone have had. The OEM wiring that was originally sending enginer information to the TCS will no longer be doing so, and I'm fine with no TCS as I'll develop a separate strategy within the Link G4+ ECU. Just don't want to lose ABS as a result. Adam with Link suggests that I won't, and he definitely knows his way around standalone ECUs, but wanted to reach out to those in a community specific to these cars.

Thanks for any help.

[BK]

No, ABS will be intact as wheel speed sensors wire directly to the traction control (or ATTESA ECU in the case of a GTR which manages ABS)

1 hour ago, JarrettL said:

The OEM wiring that was originally sending enginer information to the TCS will no longer be doing so,

Should be also still intact, as in a throttle position output from Link to traction control.

[JarrettL]

The car is an ENR34, so while not a GTR, does have the ATTESA system. In which case I may be working from the wrong wiring diagram, as the one I have has the wheel speed sensors going to the ABS/TCS control unit, and not ATTESA. Attached below.

What all does ATTESA need to see from the engine? I missed the throttle position output, but it seems that's done through position 37 on the ECU connector. Easy enough in most instances, but I'll be going to a DBW throttle. Might be another question for the Link forum.

[Unzipped Composites]

90's ABS systems are extremely over-rated. They are more-or-less an elaborate system of wheels and pulleys, clunking their way to a kind-of-but-not-really effective result. I wouldn't worry about losing it.

 

To answer your question though, my ABS worked just fine with my Link Thunder. I just ended up deleting it because it made removing my engine harness THAT much easier. And also, see above.

[JarrettL]

Oh, for sure. But I'd prefer it over nothing at all. For now, anyway. It's behavior during a track day with sticky tires and the 355/350mm Brembos will be the ultimate decider. Until then, I want to proceed with retaining as much functionality as I can, and only eliminate something whose duty is assumed by the Link, or one of the other devices I plan to run.

[Kinkstaah]

My car has a LS1 in it.

It still has ABS.

I didn't need to remove anything, pretty sure it cares very little about the car ECU, as I've also previously had a haltech ECU as well and not run into this.

[JarrettL]

I'll dig a bit tomorrow when I can go outside and peruse a bit inside the car, but I'm curious to know where the wiring is similar to a GTR because of the ATTESA commonality. So while my original concern of losing ABS may not be much of an issue, ATTESA might. I wish there were more ENR34s out there so some of this was documented.

[Kinkstaah]

I should immediately state that I have (had?.. sort of have?) a GTT. This is probably different in some way. In my car the ECUs involved appear to be seperate.

SURELY people have put aftermarket ECU's in GTR's and retained AWD and ABS though...

Sometimes there's no results about specific problems because there are no problems

[BK]

I answered your question but I will expand regarding the Link. The only thing required from the engine control unit for the R34 GTR to retain ABS and 4WD is a throttle position output from the engine management computer from pin 37 on the original ECU. A GTT also has this output from factory. Whether you are cable or electronic throttle makes no difference - it is a separate output from ECU to ABS TCU / ATTESA control unit that sends a throttle position % output signal.

On a Haltech Elite they do this via DPO2 which is routed through to the original ECU connector pin and even mapped, allocated and setup in the R34 GTT or GTR base map.  An Apexi Power FC even does this so it retains ABS or 4WD. That said according to the Link G4X R34 GTT manual ( http://linkecu.com/documentation/NGTTX.pdf ) on page 16 the original pin 37, listed as 4WD out even on a GTT is said to be disconnected and not used. This seems pretty strange as I can't imagine Link would not enable it if it was required for ABS functionality, but never the less interesting that Haltech and even a Power FC retain this output.

You need to contact Link to clarify why it isn't used, as in, does the ABS not need a TPS output from the ECU on an R34 GTT to function, with only an R34 GTR needing this output for 4WD functionality ? (which it absolutely does on a GTR).

Or you could just forget about a Link, buy a Haltech and know either way that the R34 GTT or GTR ABS / 4WD signal is supported and will work regardless and have miles better technical support than Link.

[JarrettL]

My Link is not the plug-and-play model, but is a G4+ Thunder. I'm doing an engine swap that necessitates an ECU that can control dual DBW throttle bodies and 4 camshaft position sensors, so it's either the one I already purchased and own, or it's MOTEC. At $2110 USD after taxes, this one just made more sense.

I will still take your advice and consult with Link on their forum. I hoped to spread some questions out as Adam over there is an absolute genius and I fear I'll wear out my welcome before too long. With as many pinouts as their are on that ECU, chances are that one of the PWM-capable positions can replicate TPS signal as an output.

[BK]

If your ECU is completely wire in its not an issue then as you'll be able setup a spare output to do it. 👍