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Mark
Mark, Technician
Category: Car
Satisfied Customers: 1504
Experience:  Qualified City & Guilds
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I have a Renault Laguna 1.6 16 valve last of the Mark 1s registered

Customer Question

I have a Renault Laguna 1.6 16 valve last of the Mark 1's registered in 2001. The engine started to run unevenly and I assumed one of the 4 coils had failed as this has happened before. I was driving the car to my mechanic and the car stopped altogether. My mechanic has changed the crank sensor but still no spark. He is at a loss as to what to do next. I'd read elsewhere that an amplifier could be at fault but my mechanic cannot find it and is not sure if my model even has one.

I would appreciate any suggestions you might have as to solution. Thanks. Michael.
Submitted: 2 years ago.
Category: Car
Expert:  Mark replied 2 years ago.

Mark :

Hello, my name is Mark and I will try help you with this.

Mark :

Does the engine management light come on when you switch ignition on?

Customer :

No

Customer :

It comes on initially with all the other indicators but distinguishes after a few seconds.

Customer :

It stays on now because the engine will not start.

Mark :

You just confused me by answering no, then yes but goes off and now it stays on.

Mark :

So does the engine management light come on when you switch ignition on?

Customer : Apologies, the engine management light does not come on with the ignition switched on.
Mark :

Ok

Mark :

We need to find out why that is. The engine light is switched on by the engine control unit.

Mark :

First thing is to check the fuses that supply the control unit.

Mark :

Fuse 12 supplies the fuel pump relay and the control unit.

Mark :

Fuse 60 goes to the fuel pump relay output and supplies the fuel pump and the ignition coils.

Mark :

Fuse 4 is a 60A maxi fuse that then supplies fuse 30 which in turn supplies the control unit.

Mark :

You need to make sure all those supplies are present to the relays and control unit.

Mark :

Next would be to check the ground connections for the control unit.

Mark :

If you find all the supplies are good, relays are good, the grounds are good and the engine still doesn't start you need to replace the control unit.

Customer :

Thanks, I have forwarded this info to my mechanic and I will respond once I get feedback from these actions.

Mark :

Ok

Mark :

How did you get on with this?

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