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2000 Impreza OBS
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Discussion Starter #1 (Edited)
So first before anyone jumps down my throat: yes, I have searched already.


Background: I have a 2000 Impreza OBS I bought about six months ago. Cruise control has not worked since I bought it. The cruise button on the dashboard does illuminate, but I cannot get the car to start cruising by using the stalk on the steering wheel.


So I did some searching. Seems one common problem is the missing little rubber thing in the clutch pedal that pushes the switch (see this thead). Turns out mine was missing, but I replaced it with one from a junkyard. Did not fix.

I also read in a few threads that the vacuum line from the actuator can become detached. Checked, it's on there snug as a bug, no apparent issue.

Next I thought it was the stalk itself on the steering wheel, since mine did not feel snappy like the one in my girlfriend's 1997 Legacy Outback. So I replaced that last night and went for a drive, but could not get cruise control to engage.

The only thing I can think of now is the actual cruise control module is bad. Before I go out and buy one of those, can anyone think of anything else to check out? Please help!

[Edit]
Per replies, I checked the neutral switch (I used ecuExplorer for this), but that switch is working fine.
To be checked: clutch pedal switch, brake pedal switch

I see the vehicle speed sensor in the cruise wiring, but I'm assuming if my speedo works that isn't the problem.
 

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2000 2.5RS/C BRP
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You basically went through the same exact steps as I did, and you've come to the same conclusion... Except that my CC used to work and simply turned off one day while I was using it. The car just started slowing down.

I haven't yet replaced the actuator, because... Lazy, money, etc.
 

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Discussion Starter #3
Hmm, I haven't thought about replacing the actuator, I was thinking of doing the control module itself in the cabin.

Wondering at this point how much cruise control is worth it...
 

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R56 Cooper S
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There are various things that can cause the cruise control to not work.

Besides the things you've already checked, there are:
-Clutch pedal switch.
-Brake pedal switch.
-Neutral safety switch. (located on the drivers side of the transmission)

Any of these can cause the cruise control system to not work.
 

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I kill threads!
2000 Ver 6 STI - 1996 Gravel Express
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I should look into fixing my 2001 OBS's cruise control too, but at the same time. I really don't care. It's just annoying that it doesn't work.
 

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Discussion Starter #6
There are various things that can cause the cruise control to not work.

Besides the things you've already checked, there are:
-Clutch pedal switch.
-Brake pedal switch.
-Neutral safety switch. (located on the drivers side of the transmission)

Any of these can cause the cruise control system to not work.

Do you have any info on how I can test these? I do have a multimeter.
 

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Hmm, I haven't thought about replacing the actuator, I was thinking of doing the control module itself in the cabin.

Wondering at this point how much cruise control is worth it...
I can't confirm, but I've been told that if the light on the switch comes on, the cruise module is working. The wiring for that light only shows a ground, the power is controlled by the module. The actuator also has a few safety switches that are what i think failed in mine. I tried to open it once before, but couldn't get the rusty screws off.

Do you have any info on how I can test these? I do have a multimeter.
For the clutch switch, put the multimeter in "ohm" mode, then back-prod the switch's connector, and watch the reading when you actuate the clutch pedal. I don't remember of the top of my head which way the switches are supposed to be, open when depressed or vice versa, but you should see the change. I do remember that the brake switch is two separate switches in one assembly, one for the lights, one for the cruise.

Neutral safety is the same way, though I don't remember where the plug for that one is to test, but it's fine, because according to every wiring diagram I've found, it doesn't use it. If the car's an auto, it uses the P/N inhibitor, but manuals replace that with the clutch switch.

There are a few fuses you could check too... #5 in the main box, and 30, 6, and 13 in the other one. I forget which box is which.
 

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R56 Cooper S
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The cruise control system very much uses the NSS as one of its kill switches. That is so that if you are cruising with cruise control on, and you move the shifter into neutral without pressing the clutch pedal, the car will know and won't just start revving the engine like crazy.

My car had a failed NSS, and it would do exactly that if i went to neutral.

The plug for the NSS can be found under the intake torque box, where the engine meets the transmission. It's a 2 pin brown plug, looks like this:



FYI, the gray plug right next to it is for your reverse lights.


Anyways, to test, just do as Hydrochloric said: grab your multimeter and check its ohm reading, then press the switch and check the reading again, it should be pretty obviously different.

When the switch is "open" it should show OL I believe, because theres infinite resistance. When the switch is closed, it should show either 0, or a really low reading.

Or, if your multimeter has a continuity tester with the beep thing, just put it on that mode, and when the switch is closed, the tester will beep to let you know there's continuity.

Someone correct me if I'm wrong.

*edit*

I actually have a brand new Neutral Safety Switch for an RS sitting right here (pretty sure its for an RS), and it looks like then the switch is not depressed, it is open, and when the switch is pressed, it is closed, and shows good continuity. Thing is when its actually installed in the transmission, I'm not sure if in gear, or in neutral, is when the switch itself is depressed. I'm gonna say in gear though.
 

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I kill threads!
2000 Ver 6 STI - 1996 Gravel Express
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FYI both my neutral and reverse sensors use a white plug. This was on my UK spec tranny and it's the same way on my JDM spec tranny.
 

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Discussion Starter #11
Appreciate the help, everyone. Will follow up in a few days once it's a little warmer up here in the north east.
 

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The cruise control system very much uses the NSS as one of its kill switches. That is so that if you are cruising with cruise control on, and you move the shifter into neutral without pressing the clutch pedal, the car will know and won't just start revving the engine like crazy.

When the switch is "open" it should show OL I believe, because theres infinite resistance. When the switch is closed, it should show either 0, or a really low reading.
The OL (or just "1" on some meters) depends on when the switch is open. Are they NC or NO (Normally Closed or Normally Open). The diagrams suggest the switches are NC, so they should show close to zero, then when the clutch is used, brake, etc, it should switch to OL/1.

I agree that it would make sense to use the neutral switch, but...


If you can find it, please let me know... It does show up in the ECU wiring.
 

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R56 Cooper S
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The OL (or just "1" on some meters) depends on when the switch is open. Are they NC or NO (Normally Closed or Normally Open). The diagrams suggest the switches are NC, so they should show close to zero, then when the clutch is used, brake, etc, it should switch to OL/1.

I agree that it would make sense to use the neutral switch, but...[/IMG][/URL]

If you can find it, please let me know... It does show up in the ECU wiring.
I totally agree. I've looked through the wiring diagram, along with Brian @ iWire, while trying to diagnose my own non-working cruise control issue I was having after my swap. Neither of us could really figure it out, and there were nearly no signs pointing to the NSS being the issue. The diagrams didn't show the switch as being part of the system.

After some more diagnosing I determined the only possibly issue had to be in this switch, so I ended up buying a new one (in my case, an 06WRX switch), spliced it in, and from then on my cruise control worked perfectly.

It is weird though, that it doesn't show up in the diagram, despite being part of the system.
 

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Hmm... I wonder if that's what's wrong with mine. Luckily that's a parameter I can check via RomRaider. ;) Granted I think that's harder to replace than the actuator (and I still suspect that's the issue) but it's a good thing to check.
 

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Hmm... I wonder if that's what's wrong with mine. Luckily that's a parameter I can check via RomRaider. ;) Granted I think that's harder to replace than the actuator (and I still suspect that's the issue) but it's a good thing to check.
Definitely worthwhile to check, and the switch itself is easy to replace.

When I pulled my original NSS, it had failed in the closed position, but had a weak connection so it would sometimes flash open.
 

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Definitely worthwhile to check, and the switch itself is easy to replace.

When I pulled my original NSS, it had failed in the closed position, but had a weak connection so it would sometimes flash open.
A quick check of the wiring diagram says that it's an NO switch, so when it closes the car is in "neutral". I guess in theory you could test the switch by just unplugging it, then.
 

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Is it possible the little rubber hose on the cruise control assembly just came loose? On my Forester it was doing that, cruise control would work on and off then one day it just didn't work anymore. I looked around to see that the little vacuum hose came loose and plugged it back in. Now it works every time. Now I just set it and forget it. I feel like Ron Popeil right now.
 

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Is it possible the little rubber hose on the cruise control assembly just came loose? On my Forester it was doing that, cruise control would work on and off then one day it just didn't work anymore. I looked around to see that the little vacuum hose came loose and plugged it back in. Now it works every time. Now I just set it and forget it. I feel like Ron Popeil right now.
It's happened before, but no, that's not the issue.
 

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Discussion Starter #19
Is it possible the little rubber hose on the cruise control assembly just came loose? On my Forester it was doing that, cruise control would work on and off then one day it just didn't work anymore. I looked around to see that the little vacuum hose came loose and plugged it back in. Now it works every time. Now I just set it and forget it. I feel like Ron Popeil right now.
Nope, I mentioned this in my first post but I don't blame you for not reading the whole thread. Vacuum line is connected snug on both sides, though I guess it couldn't hurt to pull it off and make sure it's not clogged or something...
 

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Discussion Starter #20
I tested the Neutral switch using ecuExplorer today and it looks like it is working fine.

Have not yet tested clutch and brake switch, will do that next week but I just don't feel like that's it.

I wish ecuExplorer would show information for those switches, and/or the cruise switch, but I guess if they all run into the cruise module itself the data isn't easily available.
 
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