Renault Megane II 2003 1,9DCI - Does not start, mainly with a warm engine.

Hello,

Renault Megane II 2003 1.9DCI 120HP

I have a problem when starting the car on a warm engine and when the car stays in the sun longer. In the morning there are usually less problems with starting. This has been happening for several months, starting a car on a warm engine takes 10 to 50 minutes. After connecting to the computer, no errors pop up. I also gave the car a week to a mechanic who deals with electronics, but he failed to repair it.

Symptoms:
-After pressing start / stop, all the lights turn on, after a while the message "Oil level ok" appears
The candle heating indicator does not show (if it shows, the car fires)
-The starter does not spin
-The fan usually turns on under the hood (it is loud and sometimes it does not turn off even after removing the card and closing the car)

To start the car, you need to keep clicking start / stop until the candle heating indicator appears.
That's how he fired this morning. [movie: 043e51dccb] https://filmy.elektroda.pl/67_1526558977.mp4 [/ movie: 043e51dccb]

Have you had similar problems, or do you know where the problem is?

Quite a typical fault, most often the fuse box under the hood is damaged (moisture, all relays from the pcb should be lifted and all relays checked), less often the cables from the engine controller to the fuse box.

I went to the garage to check these relays like you said, but I tried to start the car again, of course with poor result.
In the video, I show and describe what happened under the hood after the firing attempt.
[movie: 9f692c5c6e] https://filmy.elektroda.pl/45_1526561537.mp4 [/ movie: 9f692c5c6e]

Are the relays still to blame or maybe something else is causing it?

Weight on the box

brani wrote:

Weight on the box

You mean the fuse box to the right of the battery?

Rekin24 wrote:

brani wrote:

Weight on the box

You mean the fuse box to the right of the battery?

It is my colleague about the main ground cable between the body and the engine.

Thanks a lot for the hints, today I opened the fuse box on the right side, the fuses are ok. I found only one relay there, which I will check tomorrow.
Tomorrow I will also check the weight on the box.

The low weight on the box means that the fan is still working (even after the car is turned off) or is it the characteristic knock that can be heard in the middle of the second film?
I am asking because I noticed that as long as the fan is running, the car is very difficult to start.
It seems to me that if the fan does not turn on when starting, the car will burn without major problems.

The box needs to be halved, but seriously give it to the workshop, you can see from your posts that you can't do it yourself, but only do unnecessary work for the mechanic.