Car won’t start

[Jons1001]

Hi all, have a 2008 mk5 gti dsg. Went to the shop yesterday and after coming back to the car it won’t start so is stuck in a car park at the moment. All lights come on the dash and it turns over ever so slightly (about 1 second) but nothing. If I try to start it again soon after the last attempt it won’t turn over at all.

It does have a load of codes relating to the ignition switch but these have been there years, I actually replaced the switch in 2021 when the my first came up and they never went away.

Does this sound like ignition switch or possibly something else? Starter motor?

Was only in the shop for 10 minutes so whatever has failed has been sudden.

Edit: Cleared all fault codes and 4 codes relating to the ignition switch remain as static faults. So will give this a go.

Thanks

[MKVASMR]

Which codes? Check the battery and all of the engine fuses. If that's okay try removing the sparkplugs and turning the engine if it's smooth like butter probably the starter

[Jons1001]

Hi mate, these were the codes for the ignition switch





But as I said these were present before and after I replaced the previous switch in 2021.

This morning replaced the switch again with a genuine one this time (£75!!!) and the car didn’t start. Then tried jump leads (should have tried this first tbf) and it started up.

I thought it must be the battery so took it to be checked and battery, alternator and starter all showing as good. They did say the alternator was showing a little low at 13.75 volts at 2000rpm so could be an issue but on the way home on my OBDeleven it was showing at 14.2 so appears ok.

Completely stumped now as to why it wouldn’t start!

Unless it was the ignition switch which somehow managed to cause a battery drain? Wouldn’t have thought it could do that so quickly though 

[bacillus]

just  on an off chance if you have a second key fob see if that start the engine.

[Jons1001]

just  on an off chance if you have a second key fob see if that start the engine.

Thanks but all seems ok now. I reckon the ignition switch failed causing a parasitic battery drain which is why the car wouldn’t start after having the new switch fitted. All good now though!

[Jons1001]

So since replacing the ignition switch (with genuine VW) the car has failed to start twice in two weeks and needed jump starting.

I have noticed that since replacing the ignition switch the radio stays on when the ignition is turned to the off position and only turns off when the key is removed.

Any suggestions as to why this is happening and common causes?

Cheers

[mjmallia]

I have noticed that since replacing the ignition switch the radio stays on when the ignition is turned to the off position and only turns off when the key is removed.

This is normal behaviour

[Jons1001]

I have noticed that since replacing the ignition switch the radio stays on when the ignition is turned to the off position and only turns off when the key is removed.

This is normal behaviour

Cheers, i didn't think it was as it didn't used to do this before i changed the ignition switch. However as i say it does turn off when i take the key out anyway so shouldn't be draining the battery.

Possibly the alternator on its way out but when i had it checked a few weeks ago it was showing as good. It's a mystery!

[Jons1001]

I have noticed that since replacing the ignition switch the radio stays on when the ignition is turned to the off position and only turns off when the key is removed.

Just got back to work from lunch after driving for 10 mins and then let the car sit for 5 mins and battery dead again. Now the radio is staying on with the keys out. Do you think this could cause battery drain so quickly? This has only happened since I changed the ignition switch so maybe something to do with that.

This is normal behaviour

[Jons1001]

Still having issues. Can anyone answer this for me please?

1. If the car can be jump started does this rule out starter motor?
2. If you can hear clicking does this rule out starter solenoid?
3. If car can be jump started, driven for 20 mins, left for 6 hours, start up fine and be driven another 20 minutes, then 5 mins later won’t start….does this point to anything in particular?

[GVK]

The fact it can be jump started rules out starter motor, i'm wondering if you have a bad earth strap that goes from the gearbox to the chassis.

If it starts with a jump, it's using the earth from the other vehicle etc. Worth a try getting jump lead from body to engine/box and trying it, doesn't cost anything.

[Jons1001]

The fact it can be jump started rules out starter motor, i'm wondering if you have a bad earth strap that goes from the gearbox to the chassis.

If it starts with a jump, it's using the earth from the other vehicle etc. Worth a try getting jump lead from body to engine/box and trying it, doesn't cost anything.

Thanks for your reply.

I decided to get the battery checked again as I knew it was at least 5 years old so thought I may aswell change it anyway. Took the car for a long run and it was showing 14.3V obd11 and status was ‘charging’. 5 mins after pulling up at Halfords it was tested at 10V and obviously wouldn’t start up.

New battery fitted and started straight up, so hopefully this was the cause although after driving an hour at motorway speeds battery status is still showing as ‘charging’ so unsure if I have an alternator problem?

Was strange as 3 weeks ago when I first had starting issues Halfords check said battery and alternator were completely fine.