All electrics die when I turn ignition

[Rossimac]

Hi - hoping for some advice.

Symptoms are, unlock car with remote key fob and doors unlock with a bleep bleep. Electrics working at this point: interior lights, dashboard display (because I opened the door). Put key in ignition and turn to start the engine and it feels like when it passes position I on the ignition switch to turn on accessories, all electrics die in the car.

Nothing works, can't lock the car with the remote key fob. Interior lights, dashboard all out. Of course, the engine doesn't start either when it reaches position II on the ignition switch.

It has happened twice now in the past 3 days. I've maybe had 10 starts in this period. Both times the car has been left standing for many hours before trying to turn the engine on and it failing.

Taking the negative terminal off the battery and reconnecting fixes the issue.

Any ideas from anyone? I've read online it may be a short in the ignition switch but I'm not at all good in this area. I just want something to give my mechanic to go on :)

Thanks!

[Rossimac]

Also a VCDS scan after both occurrences revealed nothing.

[fakie1977]

Sounds like a dead battery. Do you know it’s age? Do you have a multimeter to test battery voltage and if it’s holding charge?


Sent from my iPhone using Tapatalk

[bobby_fodge]

Agree, sounds like a dead/dying battery.

Borrow one from another car and if the golf fires up you know what the issues is.

If you have breakdown cover you could get the AA or RAC to test your battery.

[colesey]

Lockdown flat battery, mine did much the same. Just buy a charger off amazon and bring it back to life. Fwiw my battery was 12 yrs old and seems to be holding its charge fine 2 months later despite next to no driving. I think only 70 miles since mid March.

[GVK]

It could well be a battery, but I don't understand why disconnecting it fixes the issue?

[fakie1977]

Probably when you disconnect and reconnect you are clearing away some of the oxidation/dirt from contact surfaces that accumulate over time. This can help if the charge remaining in the battery is really low (ie on its way out) enough to overcome the lack of charge in it. A brand or fully charged new battery would overcome this resistance more easily.

Also any “fix” would only be temporary.


Sent from my iPhone using Tapatalk

[LC5F]

Have you recently fitted a new head unit?

Mine would randomly go funny... unlock as normal, interior lights switch on with door opening, jump in, and initial turn of shows dash lights as normal and then turn key to start and suddenly the entire Golf is completely dead - I called it zombie mode.
Behaved like the battery was completely dead, but disconnect and reconnect battery and is back to normal, starts up fine as if nothing had happened and it locks/unlocks fine -  until it does it again.

Quick fix was to change its permanent live to ignition live with wires in the fuse box - https://www.mk5golfgti.co.uk/forum/index.php?topic=37977.0- long term fix is newer canbus

[Rossimac]

Hi all, appreciate the number of replies! Proof this forum is very much alive!

So this car is my 2nd GTI. The battery has started 1st time every time (and reconnecting the battery after failure, the car starts the same as normal and doesn't labour any more or anything).

During the lockdown, I would take the batteries out of all 3 cars to condition them with my charger in the house. Didn't want to pay for 3 batteries! I'll swap the batteries between the GTIs to see if that helps.

There is no oxidation on the car's battery terminals. Age of the battery from vehicle history is 2016.

I have not fitted a head unit to this car, it still has a factory RCD 300. I do have RNS-510 ready to go in along with newer battery-drain-beating CAN gateway. So, will get that fitted and hope for the best. My symptoms are exactly that of LC5F.

As GVK says, it doesn't seem to me like battery issue as a very quick battery pull and reconnection and the car works as if nothing happened. Quite strange!