Clio 172 immobiliser problem

[mark87]

My Clio refuses to start. I've just been away for a week and left the car with my local mechanic to fit new brakes while away. Not a problem. When he brought the car back last week he had to move my Nissan taxi to get the car on the drive. Everything seemed fine and he locked the car up and the taxi. Both of them have electronic locking integrated with the vehicle immobiliser and both are Renault systems.
I came out on monday morning to start the car and it wouldn't fire up and the fuel pump wasnt kicking in when the ignition was switched on.
This baffled me as its never ever done this before. Anyhow I got the mechanic to tow the car to his place lastnight so he could attempt to get it running. He rang me to say it still wasnt starting and to see if I had another key to try in case one of them had unsynchronised itself. I took the spare key and the Nissan ones as well to see if they were interfering with the car, but still nothing happening. The engine turns over but no spark and the fuel pump doesn't fire up. Also the ecu port isnt communicating with the diagnostics.
It would appear that the immobiliser has been knocked out by a spike in the electronics somewhere.
I've asked an auto electician to come out to it but have to wait til next week.
We have tried removing the fuses for the immobiliser and replacing them, have checked the inertia switch isnt faulty but still no starting.
Has anyone any suggestions of what to try next?

[Dazzabhoy]

does the central locking still work ok?

[mark87]

Yes central locking works from key fob

[mark87]

also replaced the battery in both keys.

[mark87]

apparently there is a transponder ring around the ignition key barrel. It would appear that is not working,consequently the ecu is not talking to the engine or the diagnostic port

[Dazzabhoy]

yes there is a transponder ring around the barrel if that is faulty it would not stop a diagnostic computer from being able to communicate with the ecu, do you know what diagnostic was used?

[mark87]

no, can find out tomorrow. Seems really strange.

[Dazzabhoy]

try disconnecting the battery for about 20mins then try entering into the diagnostics,

there isnt a blown fuse at all is there?

there is a unit behind the fuse box check the connections in there have had to change them before

[105Ian]

What is the immobilser light doing on the instrument panel doing when you turn on the ignition ?
It should go out after 3 secs , if it flashes when you turn the ignition on its normally a key fault to prove it is squeeze the key really hard as you turn the key as this puts pressure on the transponder inside the key and then the light will go out hopefully and then should start o.k.
If the immobilser light stays on constanly when you turn the ignition then have a look at the relays in the wet box by the battery there is 3 little relays usually black but sometimes brown these go down and will stop you getting the injection computer to power up .
If all of these are o.k. get him to check the feeds to the computer under load as the the before and after igniton feeds to the computer have a habbit of breaking down under load .
Another thing that can happen is the keys can go out of synch if the battery has gone flat on early Clio 172 and will need to be programmed again , and even though they unlock the doors they could still need doing as this was a known fault .
Hope that lot helps and let me know how you get on as know other cures as well .
Cheers Ian

[savvi]

What age and shape is the car ?

Later cars have a red flashing led in the dash.

Led flashes when immobilliser is on, ignition key in and switched on goes solid red then goes out.
Theres a chip in the keys that play up on them, i fit a by-pass module as they are very common, however it does seem strange that diagnostics don't work, check fuses under wipers on passenger side and down near the battery, both lots hidden away slightly.

Later cars are controlled by the BCM which is passenger side near glovebox and is programmed to the engine ecu under the bonnet.

On the sports there is normally also a dealer fit Sigma alarm fitted which may also be playing up, if they have this there is a extra Led (flashing red light) drilled into the dash somewhere, i've always found the module above the glovebox near the passenger airbag, but may alter depending on who fitted it.

I can supply a pre programmed by-pass module if you need it, cheaper then Dealers, i will need some info off the vin plate and inside the key to do this, it's then hard wired into the Bcm 3 wires and does away with the chip in the key.

[mark87]

Thanks guys for all the info. I'll pass it all on to the mechanic tomorrow.By the sound of things we might stand a chance of getting it going by trying the various pints raised. The car is a phase one 172. X reg, year 2000. There is an led for the sigma alarm on the gearshift console that flashes when the car is locked. The led on the dash goes off after 3 seconds but nothing else happens. The fuel pump isnt getting power to it and theres no spark at the plugs. either. We hadnt tried disconnecting the battery yet, but it had gone a bit flat due the very cold weather while I was away.
Whats a BCM? Sorry for being dense! Notr sure what I'm meant to be looking for. Is the fuse box under the wipers hidden under the plastic panel on outside of the car between the bonnet and screen?

[savvi]

Bcm is the Body control Module look like this :




That pic shows an early and late one, it's a car i have in at the moment with running problems, Renault told him it needed changing and the breaker sent him the wrong unit.


The Led you need to watch is the one in the dash, if the Sigma one is going out when car unlocked i doubt it will be that system.

Just seen the dash light goes out, so i think the relays by the bonnet is more likely, has the fuel cut off switch been knocked ? does the rev counter raise slightly when the car engine is turned over ?

If not clean or replace the crank sensor as these are also common.

[Graham]

in the end of dash fuse box check fuse box for a brown 5 amp fuse which the diagram lists as "multi tempo" remove and refit the fuse often has a poor connection which cures by removing and refitting

[105Ian]

So did you manage to get your Clio started ?

[mark87]

No its still dead! Bloody car.Tried all sorts but nothing so far. Waiting for auto electrician to look at it tomorrow.

[mark87]

Tried the multi tempo fuse several times and it does disconnect the immobiliser,but it hasn't made any difference.

[mark87]

Latest news on car is the auto electrician came out yesterday and did a few tests on all the systems. all are working so it looks like the ECU is dead. He's now waiting to get a wiring diagram to go through the Ecu circuits. I dread to think how much a new Renault ECU is going to cost. Any suggestions as to cost or if its worth going for a bespoke ECU instead.

[savvi]

How can he say it's the Ecu without any wiring diagrams ?

Do you know what he checked etc.

Where are you and who looked at it ? i know a few engineers from some other forums i go on.

Do you know what the ecu looks like, there are a couple of types one is bolted to the inner wing the other is set into the inlet manifold.
The inlet manifold one is a sealed unit and i struggled to get anyone to repair but the other type can be sent away and checked.

Renault quoted £800 to supply a new one and program on the one i have in at present, 2nd hand ecu, bcm and key £95- £200 from breakers, you need a match to all 3 item for car to start.

[mark87]

I'm near Chester mate. His name is George, italian guy from somewhere near Holywell I believe. He does all the diagnostics for Dane Motors and other main dealers round here. He did checks on immobiliser, fuel pump, central locking, coil packs,etc. I havent spoken to him as the car is at my local mechanics place still. The ECU is under a metal cover behind the battery on the left inner wing.I'm hoping that next time he comes back that my mechanic will tell me so I can go speak to him. If the ECU can be repaired then I'll go for that option. I've not actually seen what it looks like but hopefully I'll get some pics when its taken off the car.

[mark87]

I'll go speak to the mechanic tomorrow and see if I can get some photos of the ecu.I'm not sure when the electrics guy is back again as he has a load of work at main dealers during the week.

[105Ian]

I have been working for Renault for over 20 years now and have to say have looked alot of cars where people are convinced its the injection computer and it normally turns out to be the before ignition feed to the computer breaking down under load on most of the renault computers with the single plug 55 track computer normally pin 28 or 32 red wire will get 12 volts untill you plug the computer in then will drop down 1 volt under load wich will be why you can't get diagnosis with the computer . The quickest fix is then to wire a new fused live to the computer if you have any trouble getting a diagram give me a pm of the reg number and I will sort one out for you .
Cheers Ian

[mark87]

PM sent!

[savvi]

Sounds like you have the type that can be checked and repaired.

I use a company called All car electronics (01773 830895), think the charge is around £50 to check it, normal repair is around £150 ish both + vat may be trade only.
They can remove the immobilliser on them also from the engine ecu.

Did you try changing he relays around in front of the battery as they play up and the crank sensor plays up.

[avopaul]

i use ecu testing got them off ebay not bad prices

[mark87]

I've not been able to do any of the testing myself as the car isnt on my drive,its at local mechanics in the village. I'll go up tomorrow and see what else can be checked. I'll write down the info that Ian has mentioned to check so that these can be checked out.

[mark87]

As far as I know he checked all the relays and they are all ok. its the computer that isnt working I think. hard to know until he comes back with diagrams and does full check.

[mark87]

The car started this morning. The mechanic was getting the ecu off and discovered the connections to it were corroded so he cleaned them up and did some more checks on that side of it and eventually got it to start. it needs a piece of wire replacing apparently that has dissolved into green powder so waiting for that to be done later this week. Very relieved thats its something simple and not the ecu thats faulty. Thanks for all your suggestions and assistance with info.

[Firey]

What age and shape is the car ?

Later cars have a red flashing led in the dash.

Led flashes when immobilliser is on, ignition key in and switched on goes solid red then goes out.
Theres a chip in the keys that play up on them, i fit a by-pass module as they are very common, however it does seem strange that diagnostics don't work, check fuses under wipers on passenger side and down near the battery, both lots hidden away slightly.

Later cars are controlled by the BCM which is passenger side near glovebox and is programmed to the engine ecu under the bonnet.

On the sports there is normally also a dealer fit Sigma alarm fitted which may also be playing up, if they have this there is a extra Led (flashing red light) drilled into the dash somewhere, i've always found the module above the glovebox near the passenger airbag, but may alter depending on who fitted it.

I can supply a pre programmed by-pass module if you need it, cheaper then Dealers, i will need some info off the vin plate and inside the key to do this, it's then hard wired into the Bcm 3 wires and does away with the chip in the key.

Hi Savvi

I am having trouble with the chips in my phase 1 keys.
Are you still able to supply a pre programmed bypass module for phase 1 clios?

Thanks

[katana]

You are aware this thread 'died' 13 years ago and that Savvi very rarely visits here these days!