[ady2sad]

anyone got 1 as i seem to have a wiring fault causing fault codes df254 think its spiked the ecu from the oil diffuser selanoid so i need to trace the wires see excactly were they splice off to

 

[Recycled Scenic]

It's not shown in the wiring diagrams in the Haynes manual and Autodata only has the wiring diagrams for the A/C ?

 

[farmerpalmer]

What computer is df254 stored in, and what exactly do you want a diagram for, as I should be able to get one ?

 

[ady2sad]

stored in ecu showing microprocessor lost memory

need to find routes of wires from oil selanoid to ecu upto throttle body

 

[farmerpalmer]

If df254 is saved memory lost, its a fault that 90% of Meganes and Scenics have stored in its memory, normally just refers to a flat battery at some point. Nearly always ignored by the dealership, unless your car is a non starter. When you say oil solenoid, are you refering to the dephaser oil flow control solenoid, the oil pressure switch, or the oil pressure control solenoid in the auto gearbox? also can you send us vehicle type ( the 4 letters after vf1 in your vin, and registered build date of your car )

 

[ady2sad]

yes referring to dephaser oil selanoid

vin numbers vf1jaoco registered 31 3 2001

had my ecu tested and its working as it should?

so what the hell is it

and is a non starter ?

puzzled me

 

[Recycled Scenic]

Does the imobliser light on the dash flash all the time?

 

[ady2sad]

no goes off would of picked that on scan

 

[farmerpalmer]

Start with the most common, unplug and plug in your tdc sensor a few times, located underneath the thermostat housing ( top of the gearbox, held in with two ten mm bolts), particularly tricky if the vehicles an auto. Most common non start that does not throw up a dtc. Superceeded to a different connector so you have to purchase a new plug and loom as well ( about 45 quid total for both parts )

 

[ady2sad]

has spark so that rules tdc out

stop light flashing but on turn of key electric light flashes then goes off!

checked earths etc all good

just had a play after work and no fuel from injectors so guess i will check power next to them and then go for cam sensor!!!!!!!!!!!!!!1

 

[Recycled Scenic]

then go for cam sensor!!!!!!!!!!!!!!1

There isn't a cam sensor on pre 2003 Scenics that I'm aware of.

 

[farmerpalmer]

Don't think it has a cam sensor, and they don't cause a lack of fuel, tomorrow when I go back to work I'll get the relay location and a couple of diagrams, you could bridge the fuel pump relay, see if you get fuel to the rail if yes then you know pump is ok, and the issue is relay, live feed to primary or switched earth from ecu missing.

 

[ady2sad]

got fuel to the rail just not from injectors, its all related to the defassser selanoid, i bridge d it out and blew the main fuse so ive prob done the power feed from ceu or negative!

had ecu tested but they couldlnt test it fully but said that the unit was doin as it should so prob a broken wire or dead earth wire as nothing blown in ecu

 

[Recycled Scenic]

Why bridge the dephaser solenoid valve feed?

It's only a shuttle valve for the oil feed to the dephaser pulley.

 

[ady2sad]

to see if it worked didnt have my multimeter at hand at home so did it the old old fashioned way lol and buggered it lol but when i first did it i didnt have the plug in and it cured the tapping which ruled out it was faulty so the i planned tio give it a live feed until i could get my sparky mate round to deal with it but he on holiday and i need the car

 

[Recycled Scenic]

IIRC it has 2 live feeds to send the valve one way and then the other.

You say "tapping" ? you mean you have a noisy dephaser pulley?

 

[ady2sad]

no its the selanoid not operating lost its live feed

 

[ady2sad]

but now ive lost feeds to injectors thats why she not starting so need wires for them to from ecu

 

[Recycled Scenic]

no its the selanoid not operating lost its live feed

IIRC they don't have a constant feeds they are timed the solenoid doesn't constantly shuttle backwards and forwards and you can't hear it working. The Dephaser is either on or off it doesn't contantly vary the inlet cam shaft timing.

If you unplug the solenoid it has no effect on the running of the engine.

 

[ady2sad]

had new cambelt kit and pulley fitted so this rules out the pulley,but when you put direct live to selanoid goes quiet as a mouse runs perfect,so this would be the selanoid in theory?

but when plugged into original plug its like a diesel again!

so what feeds the selanoid?

ecu?
oil presuure switch?

not upto date with this engine