Won't start with knobs on (Part 2!)

[Mr Webb]

Hi All,

I think this is related to my previous post. Basically went to take the car out for a spin today and when I turned the key this time the speedo went nuts the green gear stick light flashed on the dash, the doors locked and the seatbelt bleeper started. The car wouldn't start though.

I called the recovery and they put a booster on the battery and it started but the speedo was going up in parallel with the rev counter, the seatbelt warning buzzer came on and the doors locked. The car wasn't running right and kept slowing slightly but the engine management light didn't come on.

The recovery guy cleaned the earth and the battery terminals and each time the car would only start with the booster and each time the speedo and other gremlins happened.

He tested the battery and the state of health was on the change % amount and the state of charge was 75% which is fine.

For some reason the speedo is moving and this is controlling the door locking and the seatbelt bleeper as somehow the brain is thinking the car is moving?!!

I took the car for a drive as he wanted to see if it would cut out but literally only 200m and the engine management light came on. Pulled it back on the drive and turned it off. It then wouldn't start even with the battery booster. Speedo and other electrical issues were still happening.

Eventually it started and I put it back in the garage.

I know I need to get it to Renault but at the moment it won't start so has anyone got any ideas what the heck is going on?

Is this just a battery issue?

Cheers.
David.

[smilie=thanks.gif]

 

[Kett]

David, I think the battery may be a good place to start... just as a process of elimination.

My 255 is now over 8 years old; so I elected to change the original battery at 7 years as a good measure...

...and if the symptoms return then the alternator must be at fault.

 

[Mr Webb]

Update for anyone with similar issues.

I fitted a replacement battery and the problems still remained. Then checking the voltage on all the fuses on the relays in the front. Nothing seamed irregular.

Needed a wiring diagram to check further. Many thanks to haulpa_jo for helping out with these.

As the immobiliser light was not going out we thought the non starting may be an issue with the immobiliser or the ignition. The other odd things to do with the speedo, dials etc would probably be connected if the voltage was being disrupted somewhere.

Next step was to look in the back of the car so we removed the jack and stripped out the carpet. Checked voltage and ohms across fuses and relays and got some strange readings. Removed cover on the ignition computer and checked the relays, fuses etc. Some odd readings.

Then we looked at the earth wires on the ignition computer and found that one of the earth wire securing screws was loose. Tightened it up and hey presto! Car started first time, running like a dream and with no possessed type electrical gremlins. Took her out for a blast in the sun yesterday for the first time in weeks! Good times!

One of the securing screws was probably not tightened fully in the factory and had gradually worked loose. Simples and a free fix!

An earth problem somewhere in the car was what we thought could be the problem but from starting at the front of the car with the battery and gradually methodically working backwards we found the problem.

If anyone gets the same issue it may be worth checking the earth connections first just in case.

Thanks to my mate Martin For all his help.

 

[® Andy]

Awesome that it was such a simple fix ... albeit with a chunk of effort to find it!

 

[Matt]

Glad you got it sorted.