Mk5 gti electrical nightmare

Mine has another 110hp ish on top of the stock GTI, it goes well.

 

So over 300bhp rapid.
Dsg???
That's what I'd go for I think having drove one.i do like manuals but the dsg box has gotta be the best around.
Full stainless scorpion with the dsg sounds awesome but not stupid loud.
I also would have to go for white 2 door if I take the plunge for a mk5 gti.heated leather.

 

Could be something as daft as a poor connection and reseating the module fixed it. You do basically know it has to be the gateway at this point because the chance of all those others modules simultaneously getting errors, and then simultaneously being fixed is 0. So if it breaks again then the new Gateway should definitely fix it

 

Agree the problem is narrowed down to a area that can be dealt with(if it returns)
The spare module is in the car now at all times lol.
Dont matter too much carrying spares around.my mk1 has a goody box in the boot
That would get me and others out of the sh#t
Leads,plugs,pipes,towrope,cable ties,gaffer tape etc etc lol has to be done.

 

Mines manual , 310bhp 404nm
DSG is great till the mechatronics sh1ts itself, 10 years ago that was a £900 fix!

 

I'm back and so is the problem.
Long story short charged battery to full charge weds over night.put it on yesterday and cleared issues.just for good measure got a brand new Bosch battery delivered this morning.drove about a bit today and faults have started again.not tested yet as been a bit busy(building).but I'm suspecting when it goes on the charger it will read between 2 and 3
My charger( dont know if all the same)has a lower number the more charge it has so number 8 would be dead.if this is the case the battery has lost a third of its charge since this morning.and this could cause issues as I'm sure the dsg actuators will only go for so long before they stop functioning.i know its summer no heating no headlights etc.
But I think it could be alternator now not putting charge back.cars is drawing power
And then it starts.
My daughter said why did it let her drive 100 miles before but today only done 25.
My answer because the dsg wasnt doing anything when on motorway kinda makes sense what you think.

 

What's the battery voltage when running?

 

What should it read?

 

If I'm not mistaken a healthy alternator/battery should have approximately 14-14.5V at the battery terminals with the car running and no load (no lights, heating etc.)

 

Ok will check in morning had enough of it today.
But I'm sure when it was tested before I seem to recall it was 11.8-12.4
And the bloke said that's ok.
I questioned this at the time as I thought it seemed low.and dsg will need the right running on the electric side of thing I'm sure.

 

Thats very not right, maybe when its off but not on, should be about what costel says. If its low the voltage regulator/brush pack on the alternator probably needs changing

 

Above readings (11.8-12.4) would generally be a fully charged battery with engine off.

wants to be around the 14v mark with engine on

 

Checked this morning.12.6 volts engine off
14.4 engine running.so not the alternator.
But checked battery this morning also.
And lost 2 markers on the charger from a full charge yesterday.
Stumped.some dash lights on again.
Might be a job.for the stealers.

 

Has it got an aftermarket stereo?

I read a lot on the other forum about battery drain issues when using certain type of stereos which a later gateway fixes.

If you have an ammeter check on you tube to describe how to do a parisitic draw test.

 

No aftermarket radio the factory one is still in
By the look of it.
Started it again this afternoon and had 2 less lights than this morning after topping up battery just a bit of extra charge put 2 lights out.and I reckon if I drove it round the block
The rest would go out until a bit of drain and the whole sequence will start again.
Bizarre I hate these kind of issues hard to diagnose and rectify,
But it will be found eventually.

 

Definitely something odd going on, either the gateway is infact dead or the alternator regulator is intermittent. Or both

 

Alternator regulator.i dont know much about alternators apart from they keep a constant
Top up voltage whatever.
So it's possible an irregular input into electrical system would cause issues.
If so how can this be checked.
Didnt really.want to get into replacing everything until problem goes.can be a expensive way to fix a problem.but sometimes feels like if might be the only way to go.think I might get the man back with the vagcom and code the other gateway.
He got code of the other when it was behaving so can be done.and maybe a more indepth alternator test if there is such a thing.

 

Car still not sorted.so what's been done so far.ecu checked and ok.
New battery,different gateway programmed for car,all earths checked.mobile mechanic
Has all the gear and is struggling to diagnose
Problem also can only say that signals are intermittently getting to ecu.
I'm losing the will with this mk5 even though it's not mine still p@ssing me off.
Gonna have to go with dealers I think and just pay through the nose.no choice now cant have 4 grand of scrap on the drive.and it's in the way of my building work now and to be honest right now I'd rather look at a skip.

 

I think the first issue to resolve is the battery drain/voltage level. My A3 suffers from drain too, but it's much slower and manageable with the bluetooth monitor. If I don't maintain it I get extra faults (electrical shorts, all sorts). Also I remember Ian's Mk5 GTI having some module issues after the battery went flat.

12.4V+ is where a battery should be for long term health. Mk2's don't care much. My 8V would be fine at less than 12, but I made a number of warranty claims in year 3 of 5. The last battery was still good at around 10 years with charging and a 14.5V regulator which suits silver calcium more.