Bypassing the Immobiliser on a ph2 172

[Dave Hester]

So, to cut a long story short, my ph2 172 cup will not start.

The Immobiliser light goes to a solid red when the key is turned but will not go out, cranks for 3 turns and then stops dead, fuel pump does not prime and no sign of any spark at the coil

obviously its the immobiliser thats at fault

I have researched and read hundreds of threads on here on how i can fix the problem but nothing I have tried works

So, i want to get rid of the immobilser all together in hope i can get my car back on the road, however everyone says it cant be done on a ph2 due to the canbus connections in the wiring

but....I have found this company on the internet

http://www.automotiveelectronic.co.uk/

they claim it can be done and seem very proud about it as its the first thing you see on their homepage




has anyone used these guys before???

 

[DannyR]

That's not an immobiliser fault, if it was red light would flash fast.

Check your lambda sensor wires haven't melted, I had this problem, also crank position sensor

 

[Dave Hester]

yes it is, it would still crank over if the crank and lamba sensor were buggered

 

[MicKPM]

No, its 100% not an imobilliser fault!

The light going solid red and remaining lit is the car saying the key has been recognised and accepted however there is a connection or power problem on one of the many systems and that rules out a key, code, decoder ring or UCH fault. I see this so many times and everytime the customer assures me it is 100% the imob stopping the vehicle cranking and starting it almost always ends up being a poor connection and/or broken wiring.

The vehicle really needs looking at though as it may be a simple power issue but it could be a CAN-Bus issue to which is black magic to most garages.

Mick

 

[Dave Hester]

Thanks Mick, so wish i lived a bit nearer you, as i would have had it down on a trailer by now

Think i may give this company a try and get rid of the immobiliser altogether,

had 3 autoelectricians out to it and they all say its def the immobiliser, although they prob all lack your knowledge with renaults

 

[MicKPM]

They're saying that because they don't know how to correctly diagnose the system starting with the very obvious red led that clearly states, according to the UCH fault finding manual, that its not the vehicle security prohibiting the vehicle from starting. In the end it will be something very stupid and simple.

 

[Dave Hester]

I know it will mate,

but pulling out the loom to check every wire is an utter ball ache and i have had enough now

 

[DannyR]

Just check the wires to your lambda sensor, I had the same fault!

FFS, one day someone will ask for advice get an answer and believe it. Saying that you did put a bucket in your engine bay so your at least 50% retarded

 

[MicKPM]

You dont have to go to those extremes. A diagnostic on CLIP is the best place to start as it will run a multiplex network test. This alone will help narrow down what/where the problem actually lays be it a connection or simple lack of power to a controller.

Does the EM light come on and go off at key on?

 

[Dave Hester]

already checked every sensor, fuse, earth, wire, battery, relay,

EM (is that the immo light?) flashes as normal at rest. Put the key in and turn to start and em light goes solid red but never goes out, cranks for 3-4 turns then just stops

if i put the ignition on and wait a few secs before trying to start it will not crank, again, light will not go out

you have already been a great help Mick telling me my Key, decoder, and uch are fine

just think, bypassing the immo will be a far easier fix than taking the car to a main dealer to be put on a clip to tell me I have a immo problem and told i need a new £700 ecu

 

[Jonny1*2]

Take the car to Mick, it's not that far. It WILL be a wiring fault, either Can-bus or power no doubt. To remove the immobiliser is a ball ache.

 

[MicKPM]

I seriously doubt it will need a new ecu and no, the em light is not the red led... its the amber engine management light and looks like an engine shape.

By all means bring it in... i promise you, it'll drive out and won't cost anywhere near £700!

Mick

 

[Dave Hester]

Are sorry yes that does indeed go out

 

[Sean6545]

Listen to mick, its normally a 12v feed to the ECU where it travels over the gearbox.

 

[Mike@Rentech]

Broken multiPlex wire to ecu. Simples
Wire broken in engine bay area above gearbox to ecu part of loom , white or grey wire .

 

[Dave Hester]

I am listening to Mick, and i know he could probably have it running in less than an hour.

Unfortunately have have no diagram of the ecu pinouts or wiring so i have no idea what any wire in the loom does, i have asked many people for some diagrams and offered to pay for their time to send it me via email but no one seems to be able to help, at the moment im just looking at this and thinking hmmmm

 

[Mike@Rentech]

Go further down than that broken wire is at the point the loom branches off towards front of car if you know what I mean

 

[Dave Hester]

I think i do mate, where the little black earth wire comes out.

Any wire in particular im looking at for breaks? (colour)

 

[Mike@Rentech]

Join Rentech Portsmouth Facebook page , you will find a 172 ecu pinout photo
Follow the wires that are twisted around each other

 

[Dave Hester]

Edit, a single white or grey wire? What does the big grey wire control?

 

[Dave Hester]

Excellent, thank you for the help so far, think its the white and purple wires that are twisted together

 

[Mike@Rentech]

White and purple twisted , ignore the big grey one

 

[MicKPM]

Thats the primary CAN-Bus twisted pair though i've never seen these break (here at least Mike). I tend to find they get stretched just before the main multiplug or the pins go cruddy at R65/R107.

If you have a multimeter handy, a quick way to test them would be to run a continuity test down the twisted pair from the ECM main plug back to the white connector in the engine bay fuse box. Or, if you had a scope simply see what the network output looks like via the odbii port.

Mick

 

[Dave Hester]

Right, quick update.

Im pleased to say that the problem has no been solved and finally the car will start.

It was a broken wire in the loom

Would like to say a big thank you to Mick at diamond motors, your knowledge on this problem has helped me so much and really helped me to narrow things down where to look for the problem

Also a huge thanks to Mike at Rentech who correctly guessed the exact faulty wire in the exact location in the loom. Absolutley amazing mate!!

It was the little white wire that is twisted round the purple wire and the break was 3 inches from where it branches off towards the front of the car

Thank you so much chaps

 

[DannyR]

That's not an immobiliser fault, if it was red light would flash fast.

yes it is, it would still crank over if the crank and lamba sensor were buggered

Glad to hear it

 

[Oggy997]

Doe anyone have a photo, or can show me in which area to look for this wire?

Pretty hard in the dark so a hint would be great.

 

[Oggy997]

Ok, got the wire but it isnt broke (that I can see) from the white multiplex right down to where the shielding gets thick before the split.

Bit too dark to proceed, will probably need to remove the airbox to cut more away.

 

[gudgeon]

Ok, got the wire but it isnt broke (that I can see) from the white multiplex right down to where the shielding gets thick before the split.

Bit too dark to proceed, will probably need to remove the airbox to cut more away.

Hi guys ive got the very same problem with a 2005 Clio 2.0 182 as the guy who started this thread,immobiliser light staying on solid engine only cranks for a few seconds but sometimes not at all,ive tried the reset procedures and ive stripped all the usually suspect wiring and done loads of continuity tests,checked fuses and relays etc and cant find any fault,i would appreciate any ideas on my dilema....thanks guys

 

[Andy.H]

i'm having exactaly the same problem ive checked the cables and there isnt any breaks at all so now im mega stuck

 

[JaredHasNoBrain]

Hey Guys, First ever comment or post So Brand new to forums aswell too,
I know this thread a couple of months old, But I just bought a 2003 Clio 172 with the exact same problem.
So If anyone who would be able to post a pic or anything of where this cable is So I dont have to pay a sparky my arm and my leg Please!

Thanks!

 

[Jonny1*2]

Hey Guys, First ever comment or post So Brand new to forums aswell too,
I know this thread a couple of months old, But I just bought a 2003 Clio 172 with the exact same problem.
So If anyone who would be able to post a pic or anything of where this cable is So I dont have to pay a sparky my arm and my leg Please!

Thanks!

The run from the ECU to the fuse box, then through the bulkhead to the UCH. It will most likely be the engine bay wiring, or the white connector in the fuse box. Continuity testing isn't usually good enough to check the data cables.

Are you sure you have the same issue as the OP? Where are you based?

 

[JaredHasNoBrain]

The run from the ECU to the fuse box, then through the bulkhead to the UCH. It will most likely be the engine bay wiring, or the white connector in the fuse box. Continuity testing isn't usually good enough to check the data cables.

Are you sure you have the same issue as the OP? Where are you based?

If im honest the only thing I picked up on there was ECU and fusebox, I just to know what im going in for before I pay out pretty much,
Im From Bridgend (South Wales)

 

[JaredHasNoBrain]

If anyone has looked at the loom and seen no damage, I had a sparky come to my house to look at my Clio which had the same problems and the OP,
after everything I tried it was a Fuse that has corroded, apparently its happened to 3 Clio 2.0 in south wales over the last month!
Cost £20 just for the call out, now the beauty is driving like a King

 

[MarkJones]

Hi, could you tell me which fuse? Would be a great help.

Thanks

 

[JaredHasNoBrain]

Hi, could you tell me which fuse? Would be a great help.

Thanks

Ill look later, im in work ATM
Ill be home by 4 so ill reply then

 

[Dave Hester]

There will be a break in one of the wires that are twisted together, the white and purple wires

 

[priesty84]

I had exactly same problem wiv my old saxo vtr....took me over a year to fix it...had everyone at it havin a go and nothing would....eventually I eneded up buying a brand new ecu of the internet for around 200....th company specialised in ecu's wiv the immoboliser taken off as it is a common problem with French car.....was absolutely amazed wen the car started up....it was literally my last option otherwise I was going to scrap the ca becuase I had given up on it

 

[mattyRB 182]

In the cases I have seen with this fault its usually a white wire coming from the main injection relay in the engine fuse box [1 of the 3 black or brown relays] to the injection computer that's has broken or corroded if you follow the wires from the relays to the injection computer you should find the issue. But as said would be much easier to put the vehicle on clip to get exact fault

 

[BRIGSPORT]

Been having intermitent starting woes with my 2003 172, i do have a faulty uch, however, i have found 4 wires that had rubbed through on the meatal cover that goes over the ecu multiplug, including a white and purple twisted pair. Hopefully that will sort it.

 

[BillyB1976]

I had this same problem today after a somewhat strange turn of events, lol. Early this morning I left for work at my usual time and soon noticed that my only ignition key/ key fob wasn't working and the car refused to unlock. At this point I went back indoors and replaced the transponder battery inside the key but once again upon testing the car refused to unlock. After further examination within the key and removal of the PCB I noticed that the tiny micro switch (which should be securely soldered to the PCB) had a broken solder connection on 1 side, I was then able to quickly unlock the car by simultaneously making the broken connection and pushing the switch at the same time, after this I drove to work unhindered, parked my car and left it unlocked (In a fairly secure car park) While I was at work I had an engineer friend resolder the broken connections and successfully repair me key/ key fob, I thought this was the end of my problems until I tried to start the car to drive home. The doors locked and unlocked fine but the engine would only turnover for 3 or 4 seconds and would not fire at all. After checking for and finding no blown fuses I gave up and phoned the AA. When the AA patrol man arrived he watched while I tried to start it a few times then he looked at a couple things under the bonnet and said try it now, to my amazement the engine burst into life. All he did was pull on what he called the "exciter wire" which connects onto the starter motor somewhere. At the end of the day it's not WHAT you know, it's WHO you know.