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HOWTO: ECR33 PowerFC + Active LSD

Intended Audience: Anyone with an ECR33 Skyline with Active LSD + Apexi PowerFC

Technical Level: Medium

Duration: 30 minutes

Effort: Minimal

Result: Awesome

!!!Caution/Achtung/Attenzione!!!

Follow this guide at your own risk. You have been warned. We are not responsible for any actions you take. The information contained herein is a guide and should *not* be acted upon with consultation from your local tuner (he/she may not agree with my comments / suggestions). If you are unsure or are not confident don't do it.

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https://www.sau.com.au/forums/topic/107656-ecr33-powerfc-active-lsd/
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This guide is a howto guide to correct issues with the Active LSD system featured in some ECR33 Skyline's that are using an aftermarket ECU (such as the Apexi PowerFC).

Cars that have the Active LSD factory option have the following features:

Skyline GTR Vspec Differential (finned cover)

diff.jpg

SLIP and A-LSD lights on the dash inside the tacho

tacho.jpg

Problem:

You experience intermittent A-LSD fail on your dashboard after you have fitted an aftermarket ECU to your ECR33 Skyline.

This may be because the ECU you are using is not suited to the Active LSD model. It seems the stock ECU present on the Active LSD model cars performed a TPS signal relay to the ABS/ALSD computer in the boot. The Apexi PowerFC (and possibly others) don't relay the TPS signal and therefore the A-LSD system fails intermittently. Read below for instructions on how to correct this. Please note this involves tampering with your wiring loom. You need to make sure you cut and splice the correct wires, if you do it incorrectly it could be fatal to your ECU and/or Engine so please double check, triple check or get a mechanic or someone who is confident to do it if you are unsure.

Tools:

Wire Splicer + Pliers

Phillips Head Screwdriver

Electrical Tape

Soldering Iron + Solder (ideal)

1. Undo the kick panel and ECU braket and place the ECU on the floor

2. Locate wire #38 (TPS Signal) and expose some of it's copper wire (DO NOT CUT THIS WIRE, YOUR CAR WILL NOT RUN IF YOU CUT IT)

3. Locate wire #56 (To ABS/ALSD Computer) and cut it

4. Join the car loom end of wire #56 onto the exposed copper wire of #38

5. Tape up (or ideally solder) the join so its secure

6. Tape up wire #56 going into the ECU (one end goes into the ECU, the other end should go nowhere)

Start the car up, check for A-LSD errors and all is done.

Be sure to cut the correct wires and double check, use the pinout layout to work out which way you are looking at the ECU.

It's formation is 8pin, 10pin, 10pin, 10pin, so use this in accordance with the diagram to work out which way the ECU is facing.

Special thanks to;

T04GTR and Moanie for the extraordinary efforts in getting this problem solved. Thanks guys really appreciated.

For a detailed discussion on the problems and notes check out http://www.skylinesaustralia.com/forums/in...owtopic=106326# and http://www.skylinesaustralia.com/forums/in...showtopic=28464

:yes:

wiring diagram for ecu pinouts

rb25detrec33pinout.Sun.pdf

  • 1 month later...

Cheers Paul your a legend.. I will suss it tomorrow.. I must admit in the cold weather mine rarely fails!... I took it for a bit of a flogging around and about the adeladie hills today, nothing to full on however as it has been a while since i have been in the cockpit and the alsd Light didnt come on once today.. Plenty of slip light though :(

did an awesome quarter that would have been well into the 12's at about 170 trap speed estimate... it felt goooooooooooooood! on a deserted road of course! im looking at getting out at mallala with a mate and his Ceffy pretty soon! although i am more interested in circuit and he is more interested in drift although i dont mind letting the odd thing slide :)

  • 1 month later...

Since applying this fix I have intermittently seen engine check light errors, and the TPS voltage drops to 0.02v and the revs are really unstable. a reboot of the car seems to clear the problem but i am unsure what else is affected or any other potential side affects. stay tuned

Since applying this fix I have intermittently seen engine check light errors, and the TPS voltage drops to 0.02v and the revs are really unstable. a reboot of the car seems to clear the problem but i am unsure what else is affected or any other potential side affects. stay tuned

The diff might be going into some sort of self protection mode (judging from your other thread you mean it's shutting off after 20sec) because doing burnouts/drifting etc wears them out relatively quickly. Though this is just 'what i reckon' :P

if you do a long burnout and SLIP is locked on for more than 20 seconds it gives up and goes into ALSD fail. at this stage it drops to single spinner and wont lock, until you reboot the car

if you do a long burnout and SLIP is locked on for more than 20 seconds it gives up and goes into ALSD fail. at this stage it drops to single spinner and wont lock, until you reboot the car

Yeah, my point is it goes into ALSD fail to protect itself and thus stops being an LSD.

  • 4 years later...

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