Technical Random fault codes sometimes van wont start

[s3nata16]

Hello guys first of all sorry for my English second i have problem with my van from 1 month ago sometimes wont start for several minutes and i get those fault codes u1601 u1700 u0426 p0500 p0579 p0504 also it can take weeks to again start doing this thing at the first time that happened the dashboard has gone crazy lights were coming on and going away speedo meter working and stopping i have already checked the ground connections changed the battery in addition when it wont start i see on the dashboard when i switch the ignition on not all lights come on if anyone had similar problem i will be happy to hear good ideas where to start looking thank you!

 

[s3nata16]

This are the exact codes im getting

 

[koalar]

u1601 u1700

Ignore these for now, as long as the immobiliser light goes off

When it will not start and some of the dash lights don't come on

Is it the oil, battery, engine check

When you say it will not start is that

Not turning over
Or
Not firing

 

[Communicator]

The symptoms suggest a faulty engine earth strap. This can be eliminated by connecting a temporary jump lead between the engine block, and a clean bolt on the chassis.

The photo is not mine, and was previously posted on another forum, possibly Motorhome Fun.

 

[s3nata16]

Ignore these for now, as long as the immobiliser light goes off

When it will not start and some of the dash lights don't come on

Is it the oil, battery, engine check

When you say it will not start is that

Not turning over
Or
Not firing

Its cranking but not starting i notice that glow plug light is not showing up and one more not sure if its for the immo

 

[s3nata16]

The symptoms suggest a faulty engine earth strap. This can be eliminated by connecting a temporary jump lead between the engine block, and a clean bolt on the chassis.

The photo is not mine, and was previously posted on another forum, possibly Motorhome Fun.

Will try this for sure i have seen some solutions like that with adding more grounds thats the place where i started with,those ground connections bcs there was also a problem a month ago when the bus was not even cranking the starter motor was only clicking but i found out that the battery was the problem

 

[Communicator]

Will try this for sure i have seen some solutions like that with adding more grounds thats the place where i started with,those ground connections bcs there was also a problem a month ago when the bus was not even cranking the starter motor was only clicking but i found out that the battery was the problem

See post #16 in this thread.

 

[s3nata16]

See post #16 in this thread.

Yes i understood will try adding 1 more ground strap to see if it will keep doing its thing

 

[s3nata16]

I've also forgotten to add that this begins to happen mainly when its raining snowing, idk if its a big factor or some kind of moisture is getting in places where should be dry,but i have checked places like fusebox and ecu they were dry so for now i will try with this additional earth strap and hope it will solve the problem

 

[koalar]

Its cranking but not starting i notice that glow plug light is not showing up and one more

Cranking but not starting
No glow plugs light

Got to be a clue here,

The one more would probably help also

 

[s3nata16]

Cranking but not starting
No glow plugs light

Got to be a clue here, got to be a clue here

The one more would probably help also

Yes i don't understand it either but the lights that dont come on are random for me because i think they are not always the same sometimes they do change and 1st time when it happen was while i was driving asr light came on then abs light , speedo meter gone crazy i kept driving they disappeared only left the asr light i stopped let it rest for the night on the next day no light and a week later it happen again soon after that started to this problem with cranking but not starting till now

 

[s3nata16]

Also there was one day that it didnt even wanted to crank,was only ticking like the battery or starter motor was dead and then i gave a minus from another battery only minus and it fired up instantly from then i have changed the battery and that problem is gone for now

 

[the green vanper]

then i gave a minus from another battery only minus and it fired up instantly

Earth points and cables, not only the engine to body, but battery to body and the other ones (ECU,, BCM)

Standard problem on the x250s.

I will try to upload the power supply lines afterwards.

Have you got rid of the water ingress from the scuttle tray into the engine bay problem?

 

[s3nata16]

Earth points and cables, not only the engine to body, but battery to body and the other ones

Have you got rid of the water ingress from the scuttle tray into the engine bay problem?

Do you mean that i have to double up all earths on the bus or just to check them for corrosion etc and yes i did isolate the problem with getting water in the engine bay thank you for the technical data!

 

[koalar]

Do you mean that i have to double up all earths on the bus or just to check them for corrosion etc and yes i did isolate the problem with getting water in the engine bay thank you for the technical data!

You measure the voltage at either end when under load

So for example to test the engine block earth

You would put a test lead on the block, a test lead on the negative terminal and operate the starter

Ideally it should be under .02V but I wouldn't worried 5x this

If it's okay move on, if there's excessive voltage move from the block to the eye of the cable and test again, until the voltage is around 0.2V

 

[the green vanper]

yes i did isolate the problem with getting water in the engine bay

Great!

double up all earths on the bus

Checking up visually and for resistance with a multimeter should be fine.

The large earth cables tend to rot. And also the earthing points tend to rot, so when you look at it you think you have a good earth, but there's so much corrosion on this piece of metal around the earth point that the resistance is too high. Especially the body to gearbox and the earth behind the left headlight.

 

[s3nata16]

Thank you all for the suggestions will do the tests you all told me, will check those earth straps and will give update whats going on

 

[the green vanper]

Managed to get the 2nd file.