1998 - ECU unit/ diagnostics problems - H jones
Hi, I know nothing about cars so any help much appreciated!!!

I have an S reg peugout 306 which won't start..... the diagnostics thing doesn't work so the garage can't tell what's wrong with it from that....

It had a reconditioned ECU (ECI?) unit fitted about a year ago when the car broke down with the previous owner (a friend!)

The garage it's in reckon the only thing I can do is try another ECU unit.. but there's no guarantee this will work, or how long for....

As I know nothing about cars, or garages, I'm wondering if anyone on this forum can help with any other solutions to try?!!

thanks!

Edited by Dynamic Dave on 12/01/2008 at 13:39

ECU unit/ diagnostics problems - injection doc
if the ECU isn't being powered up then the diagnostics won't work. It sound like a power supply fault & peugeots have a telecametric relay (MFU) usually brown or black about 16 pins that can give problems . Wiring looms in engine bay a little weak & crankshaft sensor are a regular occurance ,but I would recomend getting a sparky to look at the car or send ECU of for testing rather than random replacement. Have you got a plip key or key pad & is it possible its an imobilizer fault?. I would find a sparky.
Doc
ECU unit/ diagnostics problems - H jones
Thanks for the swift reply - stupid question number 1 - what is a plip key or key pad?!!!

and no 2- if I was to send it off for testing, would I do that through a Peugeot dealership?

Thanks again!
ECU unit/ diagnostics problems - Railroad.
Go back to the beginning. You say it won't start.
Is it petrol or diesel?
Do the dash lights all work when you switch on the ignition? Yes/No?
Does the engine crank when you turn the key to the start position? Yes/No

You say you don't know much about cars. From what you say it sounds like your garage doesn't either if they are guessing it's a fault with the ECU and suggest your only hope is to replace it and hope for the best.

The main relay can be a common fault on Peugeots just like an earlier poster says, and you will find it on the O/S inner wing right underneath the ECU.......
ECU unit/ diagnostics problems - H jones
Thanks railroad - it's petrol

Yes - Do the dash lights all work when you switch on the ignition? Yes/No?
Yes - Does the engine crank when you turn the key to the start position? Yes/No

ECU unit/ diagnostics problems - Railroad.

Right, from here on it might get a little difficult for someone who has limited knowledge of motor cars.

Do you have an HT spark when the engine cranks? Disconnect an HT lead at the plug, place a screwdriver in the end of the lead and wedge it so that some part of the metal shaft it is about 5mm away from the engine, but is not touching. Crank the engine and see if a series of sparks jump across the gap while doing so. Yes/No?

Disconnect the crankshaft sensor, spray WD40 in the plug, and re-connect it. Sometimes that works.

The immobiliser has also been mentioned. Does the remote work. If not switch on the ignition and press the square button on the side of the steering column cover for a few seconds to disable it. NB. This will do nothing if the remote is working properly.

From here on you're into checking injector supply and switching. A noid lamp is the easiest way to do this as long as the injector plugs are accessible. Also check that the fuel pump is running. If you have neither of these then the main relay as mentioned before might well be faulty.......

Edited by Pugugly {P} on 12/01/2008 at 15:33

1998 - ECU unit/ diagnostics problems - Screwloose
H

Garages that replace ECUs as a first step are to be avoided. [Fitted and coded, that's £800-odd on these.]

As Doc has said; if it won't talk, then the first check is ECU feeds and earths. If it still won't talk; bell through the wire from the ECU to the diag socket. Only then think about getting the ECU tested.

Your immobilizer will be a chipped key. The button on the column is only an ultrasonics deactivator. Tried another key? Ask your garage if the fuel-pump runs when cranking.

It's difficult to check spark and injectors on these as they are direct coilpack and the injectors are buried under the manifold. Only injector 4 is accessible - and not easily.
1998 - ECU unit/ diagnostics problems - Railroad.
H

Your immobilizer will be a chipped key. The button on the column is only an
ultrasonics deactivator.

-------------------------------------------------------------------
Not necessarily true. On earlier 306s the immobiliser will be disarmed by holding the button with the ignition switched on. The indicators will flash rapidly and the engine can then be started.
......................................................................
..............
It's difficult to check spark and injectors on these as they are direct coilpack and
the injectors are buried under the manifold. Only injector 4 is accessible - and not
easily.

-------------------------------------------------------------------
Not necessarily true either. Again earlier models did not have a direct ignition coil, but a DIS coil instead with conventional leads. However if it does have the direct coil (with a square 4 terminal multi-plug) you can still check if it's switching, but you cannot check for a spark without first removing it. These coil packs do fail, but they usually cause a misfire rather than non-start. The injectors are almost impossible to get to on later 206 models, but there is a muti-plug under the inlet manifold where feed to the injector can be checked, albeit with a little difficulty.......
1998 - ECU unit/ diagnostics problems - Screwloose
Railroad

I have had the odd KFX/NFX apart.....

The OP says this one is S-plate - so direct coilpack and chipped key.
1998 - ECU unit/ diagnostics problems - Railroad.
If what you say is correct then I would definitely suspect the main relay which is situated underneath the ECU. I have known a few of these to fail........
1998 - ECU unit/ diagnostics problems - peugeotrule
Hi guys.. In know we are now 6 months on from the last post but I'm having the same problem as above.. I too have petrol, but its a 1.6 1997 306 that now won't start... what I'm curious about is you mention the main relay will this still be it on the O/S inner wing right underneath the ECU for me too.. Also where exactly is the fuel pump relay as our pump is silent, its not making any noise at all yet I can smell petrol when attempting to start her so I'm assuming the pump is def working.. thanks emma
1998 - ECU unit/ diagnostics problems - Screwloose
emma

Quite a few detail changes on yours, as it's the earlier version. The combined ECU and fuel pump relay is bolted to the back of the plastic box housing the ECU.

Have a look in your VIN number for NF - something? That third letter will identify what fuelling you have. When did it non-start; what did you notice and what's been tried so far?
1998 - ECU unit/ diagnostics problems - peugeotrule
Hi again.. Sorry for not replying but the whole thing has been a nightmare.. Just checked the 3rd letter on the vin plate and its an A ...we drove it home fine, about 35 miles, moved it around a bit whilst doing bits and pieces to it. The only other thing we done was when we bought the car the central locking didn't work, I replaced the batteries, went through the process and now the doors open fine on the blipper so I must have got that right, is it possible there is a connection and if so what could I do if anything to check ? I had a guy come out and do a diagnostic on it after it just wouldn't start, he said it showed a fault with the lambda sensor but don't change it as that wouldn't stop the car from starting so i didn't. I then went to peugeot and got a main ignition relay which like you said was indeed on the back of the ECU (packet was open) they said it was the only one thay had but I could have it for £20 as it was already open. But that didn't do the trick, I went back to get a crank sensor but they talked me into putting it on their machine as they said it would be more in depth so I thought for £42 ok.. They had the car til sat just gone and to be honest that was a bigger waste of time.. They rang to tell me my coil pack had a crack in so that was the problem, £220 quid ! i said ok go ahead, they then rang me to say sorry, it hasn't cured it.. I told the chap to take it off then, he got a bit shirty but I said i am not paying £220 for a part I don't need. He then said it was my air filter that was blocked, then it was the main ignition relay, I politely told him I bought the part from them 5 days previous. Well at that point I got annoyed and said forget it, I'll have it collected and thats what I have done. I have today ordered a new crank sensor and lamda sensor which should be here tomorrow so I'm no further forward. they did say they had checked the pump and pressure and both were fine but I suppose i could take that with a pinch of salt considering the other boo boo's they made ? So I'm still without the peugeot.. Thanks for your help..

Edited by peugeotrule on 28/07/2008 at 15:36

1998 - ECU unit/ diagnostics problems - Screwloose
emma

[Put some paragraphs in it... We're not short of space.]

Are you sure that was the right relay - there are many versions. He's right; the oxygen sensor won't cause a non-start.

£220 for a coilpack!!? If it happened after moving it around; have the checked the plugs?
1998 - ECU unit/ diagnostics problems - karlhawke321
Hello, sorry to bring this up again but i havent had my car for almost 4 months now...... getting a bit desperate.

I am having the same problem as above, a few garages and mechanics have had a look at the car and they dont know what is wrong with it so i am still stuck.

Things they have checked:
coil pack
crankshaft sensor
general wiring
fuel pump

I changed the module on the back of the ecu however i am not sure if this is the right one!! is there any easy way to check this?

Also have tried three different diagnostics on the car however none of these could connect.

Have thought about getting rid of the car but simply do not have enough cash

Any help greatly appreciated
1998 - ECU unit/ diagnostics problems - TTomas
I have the similar problem
Please Help Urgent
306 1.6 TU5JP/Z engine 1993
Cold engine have no problem to start.
After 5-10km (not so hot engine) on hot days engine just stop. Start is not posible like no fuel. With Full contact II ignition switch, I dont hear usual 1-2 seconds fuel pump work.
Fuel pump don't work, no power to conector.
Double Relay module is ok, pin 10 have no ground - from ECM pin 3, if I conect pin 10 to ground Relay switch and fuel pump work.
ECM disconect Relay/Pump

After 15-20 min engine is cooled and I can start engine again.

Please anyone know ECM (ECU) logic in witch state of sensors ECM switch off fuel pump (Double relay). How to know witch sensors fault.
My local service don't find any ECM errors.
Please Help
1998 - ECU unit/ diagnostics problems - TTomas
I think I found problem.
Fresh Air intake duct (Air cleaner - front side of Water cooling radiator) was burn by radiator heat (10cm x 5 cm) and engine fresh air coming behind radiator. When engine is hot and I stop on hot days, turn off and after 5 min try to start engine will start and after 5 sec will stop and no more start is possible. ECM turns off fuel pump relay. Fresh Air sensor detects too hot air (maybe fire in engine) and disconnect fuel pump. In service they don't detect problem because front motor door is open all the time and intake air is cooled.
I fix the burn duct and test 1 hour driving stopping driving...
No problem now.

Can someone confirm this behaviour of ECM.
When ECM disconnect fuel pump?
1998 - ECU unit/ diagnostics problems - Pug Mug
This is a slightly different problem, but one which i have been told may be due to a similar fault.

The first time it happend, i was pulling up to a roundabout and the engine warning light came on and then the big red STOP light in the centre of the dash. Basically the car just cut out and wouldn't re-start. Recovery man said it sounded like it was misfiring (and would need a new coilpack) when it eventually started, so i had it towed to a garage.

ECU reported no fault and the coilpack was ok and when everything was plugged back in it worked fine!

2 weeks later everything cut out whilst i was doing 70 (which wasn't fun) I had to have it recovered to a different garage this time, and they said after cleaning a few connections that it was good to go again. the engine now sounds and feels a little rough, but not sure if that's related.

2 days later, it cut out again and this time i had a fiddle with the ECU connectors and got it going.

Basically i'm fed up of giving it to a garage, getting charged an hours labour, and then the same thing happening again!

It seems that it is something to do with the ECU and connections to the power. Can anyone tell me if this sounds plausible, if it is, is this is a common/easily repairable fault. Maybe a new connector/cable would do the trick. If this sounds too simplistic, does anyone have any other ideas?
1998 - ECU unit/ diagnostics problems - teenager2413

hi guys and girls

i bought a 306 1999 1.6 8v merdian special edtion the other day cheap

the guy i bought it from said it had stop as if it had run out of fuel

before this he replaced the ecu with a mp7.2 which got it running

i have tried starting it in many ways

there is no power going to the fuel pump and there is no spark as well i have tried testing for power on the ecu and the box behind it and there is none . any help please guys because i love this car and i dont want to have to scrap it

thank you charlie

teenager2413