Fiat Siena Diesel 1997 Buijias warming

My problem is that, my fiat siena Turbo Diesel 1997, is that the lighting light of the preheating of the spark plugs is less than the timer, the timer is well delay 13 seconds and the dashboard light warns at 5 seconds, where is the problem?
Ah and apart the engine heats me, the radiator is new the thermostat is new the electro fan turns on well, I think it is a water pump or the cylinder cover

Taking into account that you have not put the type of engine, I must assume that it is a direct injection JTD engine so the operation of the heater box is correct. Heater in this vehicle only operates in start, at temperatures less than 10ºC and after starting to refine combustion.
Regarding the car hot:
- The fans shoot at its temperature?
- Do you see the water through the expansion bottle?
- Take a lot of pressure the circuit while heating?

You already have a job ....

There are 2 versions of the prealesty: the first version was of any component in the preheating and that is why you have that problem. Then there is another preheating version in which through a bulb in the engine, it takes the temperature of the same and that gives it the preheating time in the witness light, and it warns you that it is not necessary to heat it more. You have to fix that you have! ... and with respect to the temperature set if they light the decline and high of the electro. If the radiator input and exit hose are almost at the same temperature (you check the thermostat). If everything is normal ... Change the water storage cover that carries a valve that regulates the pressure of the circuit; out there is locked

Yes, the engine is 1.7 Turbo Diesel with direct injection, what I do not understand and verifies is that the spark plug heating timer works well checks it with two new ones, but the indicator light when turning off, the spark plugs do not heat enough, therefore I must perform the heating procedure twice. The timer produces the connection sound by putting contact and disconnection when the spark plugs are preheated. My question is whether the injection pump does not work well or can the dirty injectors be?
With respect to engine heating, I think it is electric, I have measured temperatures and it is normal, the two electro speeds turn on the radiator bulb and are correct. The expansion bottle circulates the normal liquid. And the circuit does not take a lot when he heats.
Thank you very much, you will have more information that you can give me because I don't know what to do.

The preheating control is made by a black box next to the fuel filter, she works well last 13 seconds verify it, but I do not understand the relationship between the board indicator that turns on 5 seconds and does not allow the spark plugs to heat in full, in short I do not know who regulates the heating time of the indicator of the luminous board. I think the version should fail two that you tell me.
With respect to the temperature, the two speeds of the electro turn on, the input and output mengor of the radiator are at the same temperature, the deposit lid has changed it and works well that I believe must reach a pressure that indicates the lid and if it works with that pressure. The thermostat was changed by the anterior was locked in open and had the same temperature problems. The inexplicable thing is that hose measurements have 85º degrees and I do not understand where it heats, I think it is electric. Thank you very much, if you have more answers in the electric I will thank you. And my last question is: it can be that the car has a black box that has behind it from the board and it may be the fault?