CANBUS related problem?

[DaveRST]

Hi! Newbie here, my missus owns a '05 182, car ran like new until a couple of weeks ago, all started with what seemed like a coilpack problem, the car was running fine, then suddenly we got no power and it started to run like on 3 cylinders, maybe only 2 because it was rough as hell, and we had no control over the accelerator, but it did not die any time. Lumped it at about 10mph to a secondary road and stopped, car was idling fine, but when you tried to accelerate, started the rough running again... back to idle, and everything fine. We let the car run for about 5 minutes, and then, the problem disappear as fast as it appears. No more problems that day.

We parked the car at home and let it alone for like 5 days, then, when we tried to fire it up... nothing.

- No MIL light on the dashboard, not even at the ON key position.
- "Stop" engine-like red light: on.
- No starter motor, unless you move the key fast enough in the first 5? (maybe less) seconds, passing from off, to on, to start as fast as you could. Then, after about 2 seconds of cracking, the car itself shuts the starter motor off.
- Plugged the Clip diagnose system from renault, we check out the inmo, everything fine related to it. Every other ecu it's ok BUT the engine ecu. The car can't conect to it.
- Tested another ECU and UCH, same problem. Right here, we know or at least we assume that it's wiring related. The other ECU and UCH came from a runing car, and after we plug in ours, and gave then back to it original car, the car ran fine.
- I've checked every relay, every fuse, and even took the wiring cover off the ECU, and test out every +12 and earths pins. Every +12v has +12, and every earth has earth.
So... i assume... it's the 27 and 57 pins, the two can bus ones. Maybe one of the wires it's sorted anywhere...


Where do i start looking? Any tips? The missus drives me crazy every day after i came back from work, because we live in a remote and it's not a realy good conected place... so she's alone at home everyday until afternoon. Please help me with the poor clio, before she kills me. :lolup:

Ps: Sorry for my bad english, i'm from Spain!

 

[Dr HMS Derv Destroyer]

engine bay fuse box, the white connector at the bottom of it all ( R34 or something connector ) that gets heavy oxidation and caulses alsort of trouble linked to this.
allso clean all the fuses and relay pins. try again after all that. make sure the battery is not connected.

 

[DaveRST]

Yeah, i already tested that. Every conector and fuse/relay box has received a good bath of electrical contacs cleaner. The white one down under the relaybox too.

 

[lemonnobby]

You have a broken wire. Did you do the wiring checks under load so it was all plugged in.

 

[DaveRST]

Yup, the ECU checks were done under load.

 

[Vaughan]

Is the battery dead?

 

[Dan@SJM]

When you do the multiplex test, what circuits are in red?

 

[DaveRST]

Hi again!

The circuit in red was at least #107 if i can remember the number... The second one from up to bottom.

Problem finally tracked. Ended up being two main faults:

- Female engine ECU conector had a lot of pins wiiiiiiiiiide open, we dismounted the yellow protector cover, and we closed one by one using a sharpened rivet to ensure a proper contact with the ECU. That's why we had +12v and earths OK on every pin with the ecu plugged in, but the ECU wouldn't had power. Bad contact points on the ECU conector. Everybody with a similar problem had to check that appart from the usual relay and fuse checks.

- The original EMS3134 is dead. Not totally, but partially. The engine will stay at idle and don't rev, lot of lights lit up on the dashboard. When disconected from the car, we can read +12v on the pins but when we plug it, we only have about +7v!!!. We plugged again the Sirius 34 we had to make the checks last time, and put the inmo chip from the other car in our key and the car fired up and rev like it's suposed to. +12v where it should be and everything ok but the climate control, off course because is not the proper ecu for the car.

So, we checked some advert sites to find a ECU and finally ended up buying and EMS3134 from a 182 and a Sirius 34 from a 172 in one package, all for something like 70 pounds. Hardcore cheap. But, we have to copy our inmo data from the original EMS3134 and write it on our new one (and on the Sirius 34 too, that one will stay as a spare).

Thanks a lot by the way. Nice forum, i'm reading a lot and learning a lot about this pretty amazing little car.