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Mike, Technician
Category: Car
Satisfied Customers: 39198
Experience:  Tech Expert
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Renault Grand Modus 1.5 CDi Reg BG08FWY. The car started and

Customer Question

Renault Grand Modus 1.5 CDi Reg BG08FWY. The car started and whilst reversing out of garage the engine cut out. The instrument lights remained illuminated even with when the ignition key was removed. We then disconnected the battery and reconnected and just the clock light came on, nothing else. The horn works but that is the only electric thing now working. I have checked all fuses including all of them under the bonnet, but nothing is working. I have checked the battery under load and it is fine and checked all the connections. I have checked the relay on top of the in car fuse assembly, which is OK. I would be grateful for any suggestions. Many thanks.
Submitted: 1 year ago.
Category: Car
Expert:  Mike replied 1 year ago.
Hello and Welcome..
My name is***** happy to help / advise.
Im afraid with this issue, its more likely to be a computer module on the car that has failed than anything else.
You can check the wiring through - paying particular attention to the main earth cable - follow it from the battery down - to where it connects to the body -and then from the body to the transmission.
You can get such issues with the wiring as above but again, if you can't see anything , its going to be a fault that has occurred computer wise or, with the ignition unit itself. Either will need a plug in fault code test to be done as a first move.
You could get a mobile mech to it - but as a word of warning - if you do - do check to ensure he has "high end" diagnostic equipment... as the Renault have very specific protocols that wont work with low end equipment.. other than that, its a dealer you would need Im afraid.
So check it through as above and go from there.
Im sorry I cannot say it will be this or that specifically - most likely computer wise, the BCM - but again, it has to be properly checked to be sure of - and to cure this issue.
Let me know how you go..and / or let me know if you need anything further on this..
~>>~~>>~ Meanwhile now - Please do click on the "Exc / Ok rating" for me at this time.. "Thank you" in advance for that .
.. Note that you can get back to me anytime at all after doing the rating - it doesn't close you out --
Best Rgds, MIKE
Mike, Technician
Category: Car
Satisfied Customers: 39198
Experience: Tech Expert
Mike and other Car Specialists are ready to help you
Customer: replied 1 year ago.
Hello Mike - I clicked on the rating before doing a send to my reply, so you may not have got what I wrote, which was that I had done all the things you suggested before I contacted you. So I feel I'm no further forward, but do understand that the nature of the problem is difficult to diagnose remotely, but I feel I've not had value for money.
Regards Peter
Expert:  Mike replied 1 year ago.
Hello again Peter -Thank you for your reply.What else would you like me to add Peter -- Unless you have a Renault diagnostic machine that I could help you with - but most people dont have such equipment...which is why I said, if all the checks don't result in anything, you will need to have someone who has such equipment to do the job for you.....
Customer: replied 1 year ago.
I realise that Mike. I've now come to the conclusion that when I examined the battery and found a crack in one clamp and Renault had never greased the terminals when new, probably resulting in a faulty connection, that when starting the car the voltage from the alternator probably fizzed the car's computer. Feeling very frustrated. Yours Peter
Expert:  Mike replied 1 year ago.
Hello again Peter -
Im sorry I missed you when you replied.
Im not entirely sure where you are up to - but if you have a bad connection like that , I would suggest to chop that off and replace it with a new one... you can get the battery pole clamps from most good car shops.. and then try it -
If it still wont have it - try a reboot of the system... If you need to know how to do that just get back to me and I will outline that for you..
Best Rgds. MIKE.
Customer: replied 1 year ago.
Hello Mike - I gave it a rest for a couple of days as I couldn't see a way forward without going to Renault and they can't book it in until 25 Sept earliest. I did repair the battery clamp fitting and it is better than new! However, the only thing that responds is the horn. Nothing else works. I presume everything else is controlled by the computer, so I don't see how I can reboot the computer as nothing else responds. I did look at the computer and checked all the fuses on the top of it - they were all OK. There are a whole series of small relay things on the top of it - I didn't check those. So that is the state of play. Just to say that we live a mile from the nearest village and 18 miles from the nearest Renault garage.
Customer: replied 1 year ago.
Sorry - I sent the above in haste and forgot to sign it off.
If you are able to offer any ideas they would be appreciated.
Kind regardsPeter
Expert:  Mike replied 1 year ago.
Hello again Peter - thank you for your messages ( I was off Sunday Im afraid )The "computer" you are referring to - the one with the fuses on .. that is not the main Ecu - that is the BSi unit - That can sometimes be rebooted - its worth a try... If the main Ecu has suffered, that will need repair / replacement... but doing a reboot will either cure it or do no harm anyway -so its worth a try.So the reboot procedure is as follows: Whenever a vehicle battery has to be disconnected, switch off all equipment, interior lights etc, close the doors leaving the drivers window open. Switch off the ignition and remove the key ( or card ) and any diagnostic equipment. Wait a full 3 minutes before disconnecting the battery. The BSi must be allowed to go to SLEEP i.e. into "active economy mode". Do not operate any equipment on the vehicle during this time. Remember, even opening the bonnet will wake the BSi on a vehicle fitted with alarm. If the battery is under the bonnet, open the bonnet first and leave it up. ALWAYS disconnect any diagnostic equipment and do not operate any other vehicles during the 3 minute waiting period.PROCEDURE FOR RECONNECTION - Reboot.Unless otherwise instructed by Renault or TechService, you must always carry out the following procedure, often referred to as a "soft re-boot", to minimize the possibility of the BSi corrupting its own software when reconnecting the vehicles battery supply. Ensure the procedure for battery disconnection has been adhered to and importantly all BSi functions were switched off with the drivers window left down. 1 Close all doors 2 Remove ignition key if left in ignition 3 Reconnect battery. DO NOT open any doors 4 Wait 10 seconds 5 Switch on headlights through the driver’s window 6 Switch on ignition then start the vehicle and check system functions. So try that Peter and let me know -Just a point to - should you need to end up going to a garage, you dont have to use a Renault garage / dealer - just one that is capable with Renaults / have the equipment for them..Rgds, MIKE.
Customer: replied 1 year ago.
Hello Mike
I thought you might like to know what was wrong with our car, which is now running again thanks to a firm specialising in electrical repairs. It was a wire in the wiring loom from the car's ignition to the main computer, which was why nothing was working at all. Although it appeared to be in tact it was just not making the connection. Luckily when it failed the computer wasn't harmed.

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