Intermittent failure to start...

03g35coupe6mt · 03-06-2013, 04:43 PM

i had the one for the cruise control replaced already wouldnt be surprised at all if the regular one went bad as many times as the clutch gets pushed down

FearlessLeadr · 03-06-2013, 09:33 PM

Just pulled the pedal sensor switch. It's just a disconnect. No control language, so it's not the problem. Stalled in traffic today. I need this fixed.

FearlessLeadr · 03-06-2013, 10:00 PM

Also pulled the fuse and no change. I'm running out of ideas.

SouthArk370Z · 03-06-2013, 10:17 PM

If a bad clutch interlock switch is the problem, you can temporarily disconnect the connector on the switch and jury-rig your own switch until the replacement comes in. Flip your temporary switch to the proper position, start car, flip switch back to "normal" position until next start.

If you know what a 4-20mA loop is, you should be able to handle it.

Use at your own risk, not responsible for accidents or damage, &c, &c, &c.

FearlessLeadr · 03-06-2013, 10:38 PM

Quote:

Originally Posted by SouthArk370Z

If a bad clutch interlock switch is the problem, you can temporarily disconnect the connector on the switch and jury-rig your own switch until the replacement comes in. Flip your temporary switch to the proper position, start car, flip switch back to "normal" position until next start.

If you know what a 4-20mA loop is, you should be able to handle it.

Use at your own risk, not responsible for accidents or damage, &c, &c, &c.

Good idea, but it appears to have cleared up after taking apart the clutch switch and putting it back together. I have purposefully changed nothing though, so unless some piece of plastic or something was holding the connection closed, I have no idea how it's become fixed.

FearlessLeadr · 03-06-2013, 10:33 PM

OK, after pulling the clutch sensor switch, taking it apart, and putting it back together, the issue seems to be resolved. However, after looking at the internals, I don't know how the computer knew it was installed. There's no circuit components, just a simple disconnect. Hopefully this is actually the problem and not just the issue deciding to go away for a bit.

SouthArk370Z · 03-06-2013, 10:47 PM

Quote:

Originally Posted by FearlessLeadr

OK, after pulling the clutch sensor switch, taking it apart, and putting it back together, the issue seems to be resolved. However, after looking at the internals, I don't know how the computer knew it was installed. There's no circuit components, just a simple disconnect. Hopefully this is actually the problem and not just the issue deciding to go away for a bit.

Glad to hear it's working again. Keep the spare handy. It sounds like you fixed the problem (not just an intermittent that went away for a while), but the switch is likely to fail again soon.

According to the 2009 FSM, the interlock switch is a simple SPST switch - the module is looking for volts present or not. Some controls in the car are "smart", eg, window switches and SLU, but not the clutch interlock switch. Edit: Ie, the module doesn't know the switch is there until it closes.

FearlessLeadr · 03-06-2013, 11:11 PM

Quote:

Originally Posted by SouthArk370Z

Glad to hear it's working again. Keep the spare handy. It sounds like you fixed the problem (not just an intermittent that went away for a while), but the switch is likely to fail again soon.

According to the 2009 FSM, the interlock switch is a simple SPST switch - the module is looking for volts present or not. Some controls in the car are "smart", eg, window switches and SLU, but not the clutch interlock switch. Edit: Ie, the module doesn't know the switch is there until it closes.

Then shouldn't that mean that I could disconnect the switch entirely? When I press the button, it breaks the circuit, so shouldn't it just think the clutch is pressed if I disconnect the switch? I also tried a wire bridge and it didn't work.

mults · 03-07-2013, 06:34 AM

Quote:

Originally Posted by FearlessLeadr

Then shouldn't that mean that I could disconnect the switch entirely? When I press the button, it breaks the circuit, so shouldn't it just think the clutch is pressed if I disconnect the switch? I also tried a wire bridge and it didn't work.

I think that the ECU needs to "see" the switch open and close when necessary. If the switch is bridged like you say to keep it closed permanently, then the ECU does not see the change in state. I know when I try to start my car, the dash icon lights up that says to depress the clutch (switch closed) and then the car starts. If the ECU does not see the switch close, then the car will not start. It is a programmed sequence that has to happen otherwise, nada.

SouthArk370Z · 03-07-2013, 07:03 AM

Quote:

Originally Posted by FearlessLeadr

Then shouldn't that mean that I could disconnect the switch entirely? When I press the button, it breaks the circuit, so shouldn't it just think the clutch is pressed if I disconnect the switch? I also tried a wire bridge and it didn't work.

Since the bridge didn't work, it would seem that mults is right and the car has to see a transition. I suspected as much (it's not uncommon for interlock circuits), which is why I suggested using a switch.

03-06-2013, 10:17 PM	#4 (permalink)
SouthArk370Z Premium Member Join Date: Nov 2010 Location: South Arkansas Posts: 8,435 Drives: 2014 Challenger Rep Power: 324199	If a bad clutch interlock switch is the problem, you can temporarily disconnect the connector on the switch and jury-rig your own switch until the replacement comes in. Flip your temporary switch to the proper position, start car, flip switch back to "normal" position until next start. If you know what a 4-20mA loop is, you should be able to handle it. Use at your own risk, not responsible for accidents or damage, &c, &c, &c. __________________ Steering Lock Links - Search The370Z Bookmarklet - FSM @ NICOclub Mankind has progressed past the need for war but we haven't evolved that far. - NachoMahma

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03-06-2013, 04:43 PM	#1 (permalink)
03g35coupe6mt Base Member Join Date: Aug 2010 Location: East Stroudsburg Pa Posts: 183 Drives: 2010 Z / 2003 G35cp Rep Power: 17	i had the one for the cruise control replaced already wouldnt be surprised at all if the regular one went bad as many times as the clutch gets pushed down

03-06-2013, 09:33 PM	#2 (permalink)
FearlessLeadr Base Member Join Date: Mar 2013 Location: Hawaii Posts: 10 Drives: 09 370z Rep Power: 14	Just pulled the pedal sensor switch. It's just a disconnect. No control language, so it's not the problem. Stalled in traffic today. I need this fixed.

03-06-2013, 10:00 PM	#3 (permalink)
FearlessLeadr Base Member Join Date: Mar 2013 Location: Hawaii Posts: 10 Drives: 09 370z Rep Power: 14	Also pulled the fuse and no change. I'm running out of ideas.

03-06-2013, 10:33 PM	#6 (permalink)
FearlessLeadr Base Member Join Date: Mar 2013 Location: Hawaii Posts: 10 Drives: 09 370z Rep Power: 14	OK, after pulling the clutch sensor switch, taking it apart, and putting it back together, the issue seems to be resolved. However, after looking at the internals, I don't know how the computer knew it was installed. There's no circuit components, just a simple disconnect. Hopefully this is actually the problem and not just the issue deciding to go away for a bit.