Ralliart ACD ECU Help!

wtz · 13-01-2005, 21:28

Hi All,
Need a little help here. I have a US 2005 Evolution MR. This car has ACD but no AYC. I have Ralliart RA580728K2 ACD ECU and when I plug it in all three mode lights are lit indicating a fault. When hooked up to a Mut-III, fault codes 72 and 73 are indicated. This is a short or open circuit in the left and right directional valves that control pressure to the AYC clutches. Pins 14 and 15 are the directional valves. The US manual does'nt even list these codes as the car does not have AYC. How do I fix this circuit? Would really like to run this ECU. Any help would be greatly appreciated.
Cheers,

Bream · 14-01-2005, 08:03

Quote:

Originally posted by wtz
Hi All,
Need a little help here. I have a US 2005 Evolution MR. This car has ACD but no AYC. I have Ralliart RA580728K2 ACD ECU and when I plug it in all three mode lights are lit indicating a fault. When hooked up to a Mut-III, fault codes 72 and 73 are indicated. This is a short or open circuit in the left and right directional valves that control pressure to the AYC clutches. Pins 14 and 15 are the directional valves. The US manual does'nt even list these codes as the car does not have AYC. How do I fix this circuit? Would really like to run this ECU. Any help would be greatly appreciated.
Cheers,

Looks like the right part number, I list 2 Ralliart numbers for the ECU, RA580728K1 and RA580728K2, but I really couldn't tell you what the difference is as the description is in Japanese, see here

Maybe it's designed for RHD cars, so you might need to switch a couple of wires

If I was you I'd e-mail Ralliart and ask the tech department, they should be able to clear it up for you

wtz · 14-01-2005, 09:00

The car is LHD, but the fault codes don't seem to be related to this. I'm hoping that any fix for open or short circuit will cure the problem. HELP!
Cheers,

Bream · 14-01-2005, 09:26

Quote:

Originally posted by wtz
The car is LHD, but the fault codes don't seem to be related to this. I'm hoping that any fix for open or short circuit will cure the problem. HELP!
Cheers,

So are the fault codes still there when you put the standard ECU back in?

wtz · 14-01-2005, 11:08

No codes when standard ECU is fitted.

Bream · 14-01-2005, 11:44

Quote:

Originally posted by wtz
No codes when standard ECU is fitted.

In that case it must be the Ralliart ECU, prob the only people who can answer your question will be Ralliart themselves, you'll probably need a wiring mod to sort it out. Let us know what Ralliart say is the fix.

grants · 14-01-2005, 12:50

Quote:

Originally posted by wtz
The car is LHD, but the fault codes don't seem to be related to this. I'm hoping that any fix for open or short circuit will cure the problem. HELP!
Cheers,

Try simulating the directional valves with resistors connected to ground. The valve has an dc resistance of 20 Ohm so try 47 Ohm/ 5 Watt resistor, they will get warm(hot?) so take care.

This may cure the fault but it is more likely that a Proportioning Valve fault code (71 - short or open circuit) will occur.

The proportioning valve has a dc resistance of 4.7 Ohm, but normally runs at 0.6 - 1.7 Amps. Try a 22 Ohm/10 watt resistor.

If this clears the fault codes increase the values of resistors to reduce the current, and hence heating, to a acceptable level

Hope this makes sense to you, and that it works

Grant

wtz · 14-01-2005, 14:00

Holy cow, anyone have a less complex solution?

Bream · 14-01-2005, 14:08

Quote:

Originally posted by wtz
Holy cow, anyone have a less complex solution?

I told you that, e-mail Ralliart

grants · 14-01-2005, 14:16

Quote:

Originally posted by wtz
Holy cow, anyone have a less complex solution?

Sorry, tried to keep it simple !

Show my post to an auto electrician, they might make sense of it

wtz · 15-01-2005, 10:14

I guess the next thing I should do is figure out where the wires that are associated with pins 14 and 15 are going? These pins are not even supposed to be used in a non-ayc car. Anyone have a web address for Ralliart that would get me an answer in english?
Cheers,

grants · 15-01-2005, 10:53

Have a look for an eleven way connector (probably green in colour) at the bottom of the left hand "A post" (front door pillar)

wtz · 15-01-2005, 11:07

I take it this is a junction block where 14 and 15 might be?

13-01-2005, 21:28	#1
wtz Registered User Join Date: Dec 2002 Posts: 14	Ralliart ACD ECU Help! Hi All, Need a little help here. I have a US 2005 Evolution MR. This car has ACD but no AYC. I have Ralliart RA580728K2 ACD ECU and when I plug it in all three mode lights are lit indicating a fault. When hooked up to a Mut-III, fault codes 72 and 73 are indicated. This is a short or open circuit in the left and right directional valves that control pressure to the AYC clutches. Pins 14 and 15 are the directional valves. The US manual does'nt even list these codes as the car does not have AYC. How do I fix this circuit? Would really like to run this ECU. Any help would be greatly appreciated. Cheers,

15-01-2005, 10:53	#12
grants Senior User Join Date: Sep 2003 Location: East Sussex Car: A proper Evo (6RS) Posts: 4,748	Have a look for an eleven way connector (probably green in colour) at the bottom of the left hand "A post" (front door pillar) __________________ (\__/) (='.'=) (")_(") Thelonious Monk Just listen and chill out, then stop posting crap on MLR . . . . . . . .

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14-01-2005, 09:00	#3
wtz Registered User Join Date: Dec 2002 Posts: 14	The car is LHD, but the fault codes don't seem to be related to this. I'm hoping that any fix for open or short circuit will cure the problem. HELP! Cheers,

14-01-2005, 11:08	#5
wtz Registered User Join Date: Dec 2002 Posts: 14	No codes when standard ECU is fitted.

14-01-2005, 14:00	#8
wtz Registered User Join Date: Dec 2002 Posts: 14	Holy cow, anyone have a less complex solution?

15-01-2005, 10:14	#11
wtz Registered User Join Date: Dec 2002 Posts: 14	I guess the next thing I should do is figure out where the wires that are associated with pins 14 and 15 are going? These pins are not even supposed to be used in a non-ayc car. Anyone have a web address for Ralliart that would get me an answer in english? Cheers,

15-01-2005, 11:07	#13
wtz Registered User Join Date: Dec 2002 Posts: 14	I take it this is a junction block where 14 and 15 might be?