Can any one tell me how to wire my fan to come on with the Ignition as I have an ecu fault and need this to get my by until I can afford an ecu many thanks

If the fan doesn't come on, it's unlikely to be the ECU. Not completely impossible, but very unlikely. Who says it's an ECU fault (etc.)

What happens if you remove the connector to the temperature sensor (green coded sensor, on inlet mani, near the thermostat?

This is an ongoing problem and its defiantly the ecu so if anyone can just give me Guide on how to put my fan so that it comes one with ignition I will be grateful

Two wires from fan connection,

Earth one of these, and then the other to switched ignition live via a 40A relay.

If it spins the wrong way swap the connections round...

Id look more into what the problem is, IE the fan switch...

Having the fan on constantly for any long period of time will eventually burn the motor out and maybe cost you as much as an ecu to replace

It's been like this for a out 6 months and I had it reversed, I brought an ecu and i was sent the wrong one so while I'm waiting for a new one to arrive I need to drive my car, the previous guy did something with the wires behind the ecu and I would like to do it again so I can use the car in the meantime

I really really doubt it is the ECU. Find Honeymonster's thread on diagnosing Seicento fan problems, they are common.

Regarding burning the fan motor. I once run mine for one hour non-stop and it was fine. I was once told I should be more concerned about burning the motor wires.

Why does every body have to question it. It is the ecu its been diagnosed as an ecu fault the rev counter stopped working because of an ecu fault. Every thing is fixed when a new ecu is installed on the car it's just the wrong one and runs the engine horribly. So if anybody can help me put my fan on the ignition so I can drive until my new ecu arrives ill be grateful.

Why does every body have to question it. It is the ecu its been diagnosed as an ecu fault the rev counter stopped working because of an ecu fault. Every thing is fixed when a new ecu is installed on the car it's just the wrong one and runs the engine horribly. So if anybody can help me put my fan on the ignition so I can drive until my new ecu arrives ill be grateful.

Fishguy said:

Why does every body have to question it. It is the ecu its been diagnosed as an ecu fault the rev counter stopped working because of an ecu fault. Every thing is fixed when a new ecu is installed on the car it's just the wrong one and runs the engine horribly. So if anybody can help me put my fan on the ignition so I can drive until my new ecu arrives ill be grateful.

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Again see the above post, I've already explained how to bodge the fan on...

To be honest people are probably reluctant to help due to the way the question was asked.

I'm very sorry if I am rude I am very stressed out and I was just looking for a straight answer,

Behind the ecu are some wires that go into some fuses and the guy that bodged it on before did it with these wires I was hoping for somebody to be able to give me an easy guid on how to attach these wires so that the fan will come on with the ignition like it has done before. I am new to cars and again I apologise for my rudeness in my before posts.

put the old ECU back unless it is a micro ECU the fault is in a connector

I purchased a brand new Ecu, and when I installed it everything worked fine, but I failed to do the set up process correctly so I had to send it back. Now they have sent me the wrong ecu and it doesn't run my car very well, I only noticed it was the wrong ecu after an hour of trying to start my car. So while im waiting for the correct ecu I have a very important trip to go on and I need to drive I just can't remember how to put my fan so that it comes one with the ignition.

There are 2 orange relays behind the Ecu. Find out which one is for the fan and remove it. Make up a patch lead with 2.5mm cable and 1/4" male blue spade connectors on each end to bridge the relay receptacles.

I'm very sorry but I'm a complete noob when it come to electronics. But I'm sure the guy just moved a couple of wires around :s

Again, what happens if you disconnect the connector off the engine temperature sensor and start the engine?

I haven't tested that and wouldn't know where to start to be honest. I already know what the issue with the fan is I just need something to get me by until I can get my ecu sent to me

Thing is, if you can't find a connector and separate it (which, all being good, should turn the fan on with the ignition), how can we tell you how to rewire it? It's like trying to teach a 5 year old how to defuse a bomb.

If I say I don't think it's the ECU, it's just me being an opinionated arrogant old bastard. But I'd guess that there are less than 20 people on the whole planet who know that ECU better than Woj, and that 15 of those work for Marelli -- the manufacturers. If he says it doesn't seem like the ECU, I'd take it very, very, seriously.

But, back to basics. For the motor to be on continuously it needs an earth connection -- a wire straight to the main earth on the driver's side inner wing will be fine, and a fused connection to a switched live. You can find a live that'll do the job with a 12v tester from Halfords, who'll sell you the cable, connectors and whotnot. 25 amps should be fine for the fuse -- they do in line ones. Do not attempt it without the fuse -- you stand a good chance of setting the car alight.

Just make sure that the switched live (goes off when the ignition is off) is a fairly substantial cable or it'll just burn out or pop another fuse. Something around 3mm thick will do.

fingers99 said:

If he says it doesn't seem like the ECU, I'd take it very, very, seriously.

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I did not say that because I know the ECU so well, only because I know fan problems are very common for MPIs. In fact, I have two fried MPI ECUs on my desk, only one of which I fried myself. So it is possible, it's just I find it hard to believe, that's it Also following somebodyelse's (sorry, too lazy to scroll back) remark - these ECUs have very dodgy connectors that easily break the ECU pins (again, I have broken connection pins on two of the ECUs in my collection). Maybe that's all there is to it?

Anyhow, a question to the OP: what exact kind of the ECU it is and what are you going to do with the allegedly broken one? I am willing to take over possession for reasonable money (perhaps p&p only ).