I seem to have a dodgy fuel cut out switch on my 96 406 XUDT (the one under the bonnet on the nearside). It seems to trip into the off position when I'm trying to start the car and takes loads of tries pushing it in and out until it clicks back into the on position (when I hear the fuel pump switch back on). Once the car is running it's fine.
This is the second time I've had issues with a fuel cut off so I'm wondering if I can just bypass it? If I disconnect it and then just join the two wires together will that work?
Cheers!
fuel cut out switch
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- steve_earwig
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Re: fuel cut out switch
I've no experience of them but I suspect you'll be fine. They don't seem to do anything other than kill the power to the ecu & fuel pump in the event of a shock (crash, bump in the road, sneeze). A lot of 406s didn't even get one, my 2.1td didn't.
Not finding a 406 XUD9 wiring diagram but there's an 11 here http://www.autoelectric.ru/auto/peugeot/406/p8c/p8c.htm the 1.9 is probably similar, you're looking for 1203 which is right next to the double relay above the ecu. There is an XUD9 diagram for an 806 on there but it shows 3 wires - the third seems to head off to the central locking unit
Not finding a 406 XUD9 wiring diagram but there's an 11 here http://www.autoelectric.ru/auto/peugeot/406/p8c/p8c.htm the 1.9 is probably similar, you're looking for 1203 which is right next to the double relay above the ecu. There is an XUD9 diagram for an 806 on there but it shows 3 wires - the third seems to head off to the central locking unit

Talking bollocks sin©e 2007
2004 D9 2.0 HDi 110 Estate lhd VF38ERHZF81657352 - sold but being very well looked after.
1991 Yamaha TDM850 - fuel leaks galore!
2008 Toyota Recall4 2.0 VVTI ATM LHD JTMBH31V90D007261 - flimsy piece of crap.
1953 Matchless G3LS - Can somebody stand by with an extinguisher?
2004 D9 2.0 HDi 110 Estate lhd VF38ERHZF81657352 - sold but being very well looked after.
1991 Yamaha TDM850 - fuel leaks galore!
2008 Toyota Recall4 2.0 VVTI ATM LHD JTMBH31V90D007261 - flimsy piece of crap.
1953 Matchless G3LS - Can somebody stand by with an extinguisher?
Re: fuel cut out switch
It's a weird one. If the car is used regularly there's not a problem but if it's left for a few days it will trip and then be a sod to reset. Don't really want to be hacking at wiring until I'm sure it can be bypassed without a problem.
Would you happen to know what's inside the switch? I'm thinking of giving it a WD40ing to see if that helps.
Would you happen to know what's inside the switch? I'm thinking of giving it a WD40ing to see if that helps.
- Doggy
- Mod with a 2.2 HDi, De-Fapped!
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Re: fuel cut out switch
Didn't think XUD's had lift pumps, or am I missing something?
2003 HDi 2.2 6-speed Exec Estate
Re: fuel cut out switch
It cuts off the fuel to the injector pump.
- steve_earwig
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Re: fuel cut out switch
1208 diesel injection pump (advance corrector, fuel cut-off solenoid).
I guess it's like Siemens injection, no lift pump so they have a primer bulb to get the fuel to the injunction pump. Or gravity perhaps...
I've no idea what's inside the cut out switch, I'm guessing it's a weight on the contacts, so if there's a sudden sideways force the weight gets dislodged and the contact broken. Or maybe it's JFM
anyway a lot of 406s didn't have them so I don't think they're essential.
I guess it's like Siemens injection, no lift pump so they have a primer bulb to get the fuel to the injunction pump. Or gravity perhaps...
I've no idea what's inside the cut out switch, I'm guessing it's a weight on the contacts, so if there's a sudden sideways force the weight gets dislodged and the contact broken. Or maybe it's JFM

Talking bollocks sin©e 2007
2004 D9 2.0 HDi 110 Estate lhd VF38ERHZF81657352 - sold but being very well looked after.
1991 Yamaha TDM850 - fuel leaks galore!
2008 Toyota Recall4 2.0 VVTI ATM LHD JTMBH31V90D007261 - flimsy piece of crap.
1953 Matchless G3LS - Can somebody stand by with an extinguisher?
2004 D9 2.0 HDi 110 Estate lhd VF38ERHZF81657352 - sold but being very well looked after.
1991 Yamaha TDM850 - fuel leaks galore!
2008 Toyota Recall4 2.0 VVTI ATM LHD JTMBH31V90D007261 - flimsy piece of crap.
1953 Matchless G3LS - Can somebody stand by with an extinguisher?
- GingerMagic
- 3.0 24v
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- Joined: Fri Apr 06, 2012 9:02 pm
- Location: Bournemouth
Re: fuel cut out switch
I just Googled it, and surprise surprise Google sent me to a page full of broken down Fords in 'Murica...
Its seems quite a common thing to do - just joining the wires together will bypass the switch and fool the engine into starting, as long as you join the correct wires of course...
Good luck in sorting it.

Its seems quite a common thing to do - just joining the wires together will bypass the switch and fool the engine into starting, as long as you join the correct wires of course...

Good luck in sorting it.
1999 T4 family wagon, slow as a turd but the kids like it
2002 Citroen Xsara Picasso Hdi90 - Dirtied by the kids, Dented by the wife....
Sadly sold the 406, best cars I have ever owned
PP2000 user, can help with faults / diagnostics in the Bournemouth area.
2002 Citroen Xsara Picasso Hdi90 - Dirtied by the kids, Dented by the wife....
Sadly sold the 406, best cars I have ever owned
PP2000 user, can help with faults / diagnostics in the Bournemouth area.