ACD System Issues (constant stand-by mode after number of attempts)
Apr 21, 2013, 01:07 PM
#1
Evolving Member
Thread Starter
Join Date: Aug 2010
Location: SoCal
Posts: 164
Likes: 0
Received 0 Likes
on
0 Posts
ACD System Issues (constant stand-by mode after number of attempts)
Culprit: 2006 Evo IX
Problem: ACD keeps going into stand-by mode (3 setting lights - tarmac, gravel, snow)
Attempts to rectify:
1. Reset ECU (disconnect battery)
2. Bleed ACD manually
3. Bleed ACD electronically
4. Replace ACD pump with a pump with only 13k miles
5. Swap ACD ECU since mine was tuned and it was the only thing that changed in the ACD system since two events ago. ACD worked fine for two event's after the ACD tune.
6. Checked ABS sensors for broken wires or anything out of the ordinary
7. Checked resevior level
Things to consider:
1. No DTC's present on Evoscan
2. Pressure switch column on data log shows 0 the whole time. Is this normal? Evo scan calls it out as a confirmation switch for high and low pressure.
3. The data log is showing a correlations between the mA sent to the center differential solenoid and TPS / Steering angle etc. But, after 30 seconds up to 2 minutes, the mA falls off a cliff.
4. Oil Pressure in the accumulator stays constant at 72 psi. Is this normal?
The data log can be downloaded here for reference:
https://www.dropbox.com/s/p4gwwany06...9_19.41.37.csv
Questions:
1. Has anyone had an ABS sensor fail without it throwing a code?
2. Are the differences between the wheel speeds on the data log normal? Is there a plus/minus tolerance that it needs to be in so it doesn't throw off the ECU?
3. Are there any relays associated with the ACD?
4. Is there something I'm overlooking?
Thanks in advance. I appreciate any feedback on similar issues.
Problem: ACD keeps going into stand-by mode (3 setting lights - tarmac, gravel, snow)
Attempts to rectify:
1. Reset ECU (disconnect battery)
2. Bleed ACD manually
3. Bleed ACD electronically
4. Replace ACD pump with a pump with only 13k miles
5. Swap ACD ECU since mine was tuned and it was the only thing that changed in the ACD system since two events ago. ACD worked fine for two event's after the ACD tune.
6. Checked ABS sensors for broken wires or anything out of the ordinary
7. Checked resevior level
Things to consider:
1. No DTC's present on Evoscan
2. Pressure switch column on data log shows 0 the whole time. Is this normal? Evo scan calls it out as a confirmation switch for high and low pressure.
3. The data log is showing a correlations between the mA sent to the center differential solenoid and TPS / Steering angle etc. But, after 30 seconds up to 2 minutes, the mA falls off a cliff.
4. Oil Pressure in the accumulator stays constant at 72 psi. Is this normal?
The data log can be downloaded here for reference:
https://www.dropbox.com/s/p4gwwany06...9_19.41.37.csv
Questions:
1. Has anyone had an ABS sensor fail without it throwing a code?
2. Are the differences between the wheel speeds on the data log normal? Is there a plus/minus tolerance that it needs to be in so it doesn't throw off the ECU?
3. Are there any relays associated with the ACD?
4. Is there something I'm overlooking?
Thanks in advance. I appreciate any feedback on similar issues.
Last edited by Johns_EVO_IX_SE; Apr 22, 2013 at 10:59 AM.
Apr 22, 2013, 12:58 PM
#3
If an ABS sensor wire is broken (not visibly, but internally) and there is an open circuit you should have the ABS light on. At least thats been my experience with internal opens on mitsubishi's.
Can you hear the pump cycle when you key on in the morning? If not, then does the oil pressure still show 72.5? First thing I would suspect would be the pressure switch. Reading the ACD system schematics I have, the pressure switch is analog and its pretty unlikely it would stay static as steady as it is.
Can you hear the pump cycle when you key on in the morning? If not, then does the oil pressure still show 72.5? First thing I would suspect would be the pressure switch. Reading the ACD system schematics I have, the pressure switch is analog and its pretty unlikely it would stay static as steady as it is.
Thread
Thread Starter
Forum
Replies
Last Post
tsitalon1
Evo X Engine Management / Tuning Forums
29
Sep 14, 2010 07:33 PM