Clutch Switch..... what does it do??

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

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Bailes1992
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Re: Clutch Switch..... what does it do??

Post by Bailes1992 »

I'm getting some serious fuel economy now I've unplugged it!
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rwb
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Re: Clutch Switch..... what does it do??

Post by rwb »

Really?
It's not the EcoMax? :P

After not reaching a conclusion above, I decided to plug back in.
On my next fill I'll be out of Millers Diesel Injector Cleaner, so I need to run on plain diesel for a couple of tanks to see if that made any difference, then I'll un-plug again and run that for a few tanks.

Current: 407 2.2 HDi 170 & C6 2.7 HDi.
Former: 406 1.9 TD; 406 HDi 90; 407 2.2 160; 307cc 180; 508 HDi 140.
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lozz
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Re: Clutch Switch..... what does it do??

Post by lozz »

If the clutch switch was disconected wouidnt it flag up aFault code, something like P0704

itss got to be there for a reason, My understanding is,the ecu reads from it and lowers the fueling when you dip the clutch to change gear etc,
so there for id say, saves fuel,

if someones getting better mpg by unpluging it, wouidnt that sugest the switch is faulty ?
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Re: Clutch Switch..... what does it do??

Post by rlees85 »

Does this cause problems on Bosch systems too? Going to unplug mine later I think!
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Re: Clutch Switch..... what does it do??

Post by GingerMagic »

I don't think the switch is faulty as when it is plugged in and you dip the clutch everso slightly, you can feel the car " pick-up" a bit, so the switch is doing something. Mpg is better unplugged as less throttle is needed to get it going as the flat spot as you pull away has gone.
It did flag up a fault code when I was getting car checked for poor performance ( throttle cable slack - honestly..!! ) but chap at garage didn't really go into detail.
Lozz is right, it is there is turn off cruise when changing gear to avoid over-revving, and to lower revs and fuel when changing gear too.
I have no cruise control and I have changed my gearchange style to accomodate the occasional splutter when dipping clutch, only when cold though, so quite happy its unplugged.
P.S. What is the Ecomax?
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Re: Clutch Switch..... what does it do??

Post by Doggy »

rlees85 wrote:Does this cause problems on Bosch systems too? Going to unplug mine later I think!
Might stop your cruze cruzin, or if it doesn't, you may wish it had. Caution Advised.
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lozz
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Re: Clutch Switch..... what does it do??

Post by lozz »

ive just been looking at some Renault, tech stuff,

the none cruise control models have that same thing on the pedal that the 406 as got, one green wire and one pink going to it,
it refers to it as being a Anti-stall switch :roll:
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Re: Clutch Switch..... what does it do??

Post by plod »

I think I need to check my clutch switch out, as when Doggy checked my car out it had 3 temporary faults and one permanent fault, the latter being the clutch switch

No chance today as too much wet stuff out there
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Re: Clutch Switch..... what does it do??

Post by rwb »

Filled up and clutch switch pulled, so let's see what -- if any -- difference it makes.

Current: 407 2.2 HDi 170 & C6 2.7 HDi.
Former: 406 1.9 TD; 406 HDi 90; 407 2.2 160; 307cc 180; 508 HDi 140.
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Re: Clutch Switch..... what does it do??

Post by rwb »

No difference to MPG.
Fault code "P0704 Clutch Switch Input Circuit Malfunction" is logged, but doesn't cause EML and limp.
Conclusion: leave it as Peugeot intended it.

Current: 407 2.2 HDi 170 & C6 2.7 HDi.
Former: 406 1.9 TD; 406 HDi 90; 407 2.2 160; 307cc 180; 508 HDi 140.
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