P0705 Read all I could find just had some more questions.

[zdigg]

I recently acquired a protege5 on the Cheap from a guy because it had a couple of "Easy problems" He didnt feel like dealing with.

anyway...

the first thing I did was run the codes.

P0705 and P0507 which is the Neutral and high idle code.

So, I cleaned the egr and Idler and inspected the transmission sensors.

Both the backup switch and the Neutral switch had torn cables. I have replaced both. as well as the cabin side switch on the clutch itself.

I have driven 5 miles only for the CEL to return, now it is only showing the P0705 neutral issue... Where do I go from here, I have see alot of "replace harness" answers and I am really hoping there is something I missed because I do NOT want to do that.

 

[pcb]

You should just simply replace the wires from the neutral switch to the ECU. It is a very simple circuit that doesn't connect with any other circuit. Just cut the wires about two inches back from the neutral switch and splice in two new wires. (check that the switch is operating properly with an ohmmeter in and out of neutral first) Then splice into the big connector on the ECU a few inches back from the connector.

It's the pink wire with a blue stripe,... pin #64. (It changes color after some connector somewhere along it's trip to the neutral switch,... that's why it's also labeled <B/L> (black with a blue stripe)). Verify the wire with it's orientation in the big connector to make sure you've got the correct one.

Don't worry about the routing of the original wire and all of it's connections. The wire goes nowhere else and is no part of any other circuit. Just run the wire from the ECU through the firewall anywhere then to the switch.

The ECU is under the front passenger floorboards and is quite accessible. You don't have to disconnect the big connector,... just find the wire , cut it and splice in. The second wire is just ground and can ground anywhere, either under a bolt at the ECU or even on the chassis near the neutral switch itself. There is no + or - on the two wires coming from the switch. The switch doesn't connect to chassis ground at the switch, it grounds at the ECU instead so it doesn't matter.

I hope you do this and I'm 97.6% sure it will work for you,... then I can prove to sneakypete that it does work without having to do it to my car to prove it to him. He's been dealing with the P0705 code for a year now.

It's a half hour fix if you're efficient.


P.S. Your high idle may have been a result of the bad wire on your neutral switch,... the car needs to know that you're in neutral or the clutch is in before it will "tell" the car to go to idle.

If this doesn't fix your problem,... then do the same thing with your clutch switch.

(I tried to type the B/L with it's brackets but it made everything all bold,.. too lazy to fix it)

 

[zdigg]

You should just simply replace the wires from the neutral switch to the ECU. It is a very simple circuit that doesn't connect with any other circuit. Just cut the wires about two inches back from the neutral switch and splice in two new wires. (check that the switch is operating properly with an ohmmeter in and out of neutral first) Then splice into the big connector on the ECU a few inches back from the connector.

It's the pink wire with a blue stripe,... pin #64. (It changes color after some connector somewhere along it's trip to the neutral switch,... that's why it's also labeled <B/L> (black with a blue stripe)). Verify the wire with it's orientation in the big connector to make sure you've got the correct one.

Don't worry about the routing of the original wire and all of it's connections. The wire goes nowhere else and is no part of any other circuit. Just run the wire from the ECU through the firewall anywhere then to the switch.

The ECU is under the front passenger floorboards and is quite accessible. You don't have to disconnect the big connector,... just find the wire , cut it and splice in. The second wire is just ground and can ground anywhere, either under a bolt at the ECU or even on the chassis near the neutral switch itself. There is no + or - on the two wires coming from the switch. The switch doesn't connect to chassis ground at the switch, it grounds at the ECU instead so it doesn't matter.

I hope you do this and I'm 97.6% sure it will work for you,... then I can prove to sneakypete that it does work without having to do it to my car to prove it to him. He's been dealing with the P0705 code for a year now.

It's a half hour fix if you're efficient.


P.S. Your high idle may have been a result of the bad wire on your neutral switch,... the car needs to know that you're in neutral or the clutch is in before it will "tell" the car to go to idle.

If this doesn't fix your problem,... then do the same thing with your clutch switch.

(I tried to type the B/L with it's brackets but it made everything all bold,.. too lazy to fix it)

I would like to add, that the car now gives no indication of the issue other than the engine code. what led me to check the sensor in the first place was when you pressed the clutch in the idle would drop after warm up(bad) that led me to clean the egr and the idler(which did smooth the idle) but did not resolve the issue. I then replaced the back up switch(which i had thought was the neutral safety switch) that also did not resolve the issue. now having replaced the backup, neutral and DTC sensor, All is well and the car runs perfectly( I now know the reason behind the cheesy "ZoomZoom" line.

I mean perfect great fantastic... I am almost 100% sure the computer is reading the signal from those sensors. in fact I can go unplug the neutral safety sensor and the clutch idle drop will start again. go plug it back in and it goes away...

Maybe I should just ignore the light if I can some how stomach it staring me in the face.

 

[pcb]

I'm a little confused,... the idle is supposed to drop (to 720 RPM for a standard transmission) when either the clutch switch or the neutral switch has been engaged.

If your RPM is lower than that, your IAC valve may be the issue.

P.S. A little piece of black electrical tape will stop the staring,... but you will have a problem when emission time comes around.

 

[zdigg]

Oh, kansas has no emission laws... Love my state, I actually don't have to run a cat at all, which is usually the second or third thing I do on every car I own.

So its actually not working if the idle stays and 900 no matter what? how was it dropping the idle before if neutral switch was totally disconnected? when it drops it goes down to say 400 or so.

 

[pcb]

So its actually not working if the idle stays and 900 no matter what? how was it dropping the idle before if neutral switch was totally disconnected? when it drops it goes down to say 400 or so.

I'm guessing the ECU is taking over control and trying to maintain a proper idle.

I'd try half a can of seafoam poured slowly into the disconnected big brake booster vacuum line then an IAC (idle air control) cleaning.

 

[pcb]

 

[pcb]

I just remembered,... when I disconnected my battery my idle was all over the place while the ECU relearned the car. It takes about 50-100 miles for the car to figure itself out again.

Your car could be struggling with the same thing as well. (but I still think the seafoam is a good idea)

 

[zdigg]

I actually seafoamed and cleaned it already, is it possible that if I just drive it awhile the code will go away?

 

[pcb]

Yes,... Very possible. My car was stumbling like crazy,... dropping right down to about the same 400 rpm mark almost stalling.

Run it for about 100 miles before you plan your next step.

 

[pcb]

You don't want the code though,... the car should be stumbling while it's learning.

If the code is there it won't try to idle itself. You should rub the code or disconnect the battery (for about 10 minutes,.. with the interior light left on to drain the ECU). Then start over fresh.

 

[zdigg]

Alright went and drove the car, when I went to start it, the clutch pedal sunk to the floor with negative pressure, I pumped it back up and now it seems to be fine... will a failing clutch system be responsible for the code?

 

[pcb]

I really don't think so,... I'm pretty sure you've got two separate issues. Unless you broke your clutch switch or something like that. I know there is two separate switches on either or both the brake and clutch pedal,... their are separate ones for the cruise control circuits.

You may very well be able to "fix" your clutch pedal with a simple flush. The bleeder screw is behind the rad. When I bleed mine I thought I broke something because it felt so different. It's way smoother now and easier to push the pedal.
You might have some grit or dirt breaking the seal in the clutch or slave cylinder. A flush might wash it out.

Here's a pic of the bleeder screw you can reach it easily from the top.

 

[zdigg]

Okay so update, on a whim I decided to swap the DTC sensor(cruise) back out with the old one, clear the code, and then I went driving. I read somewhere that it has to go in and out of neutral 10 times over 20 miles and hour, well I drove around town about 15 miles and hopped in and out of gear 20+ times at above thirty, no CEL yet. but it seemed like I had driven it quite a bit before yesterday only for the CEL to kick on this morning.

also, the clutch issue mysteriously went away, I will probably bleed the line sometime soon. I am guessing that it is just dirty as per the doctors orders lol. In my experience clutch cylinders tend to just die, they don't magically come back to life.

 

[pcb]

I'm not sure what you mean by the DTC sensor (DTC stands for diagnostic trouble code in the manual).

 

[pcb]

Did you do the frequent stops part ??? How was your idle ???

 

[zdigg]

I am sorry its the cruise disengage sensor on the clutch pedal... and I did do frequent stops Im pretty sure.

 

[pcb]

Sounds like you're on the right track. I'd just give it some time if your car learns anything or throws a code.

 

[zdigg]

Well, same problem this morning, could a cold morning be a factor here? I'm running out of ideas, how could that code not throw last night, I put 20 miles on it and put the car in to neutral and stopped a ton...

 

[pcb]

Sounds like you need to replace the wire,... The ECU isn't getting a proper signal from the neutral switch.

The weather could possibly affect the wire itself by shorting or opening the harness based on temperature, vibration whatever ??? Or the ECU may possibly wait for an engine shut-off to establish a full drive cycle ??? (The ECU doesn't really have too much documentation available for it,... it's really kind of a magic box)

The wire replacement really isn't that big a job,... cut the pink/green wire,.. splice in a new wire,... run it through the firewall,.. connect it to the switch,... connect the other wire from the switch to ground (ground it anywhere you want). You could do all that in less than half an hour.