[Koicarpkeeper]

We've been having issues with our Touran for a while starting because it is sat nearly all the time with just the odd short trip. So I've been putting the battery charger on now and again and it's been fine.
However, a few weeks back I took the dog to the vets which is a round trip of near 50 miles. The next day it wouldn't start but the battery was fully charged. Stuck the charger on later and it fired up fine a few hours later.

So now to the present situation, the car will not start. Turn the key and the dash comes on as normal but nothing when you turn the key to activate the starter. The battery has good charge and no headlight dimming when turning the key.

So tonight I took the air box out to see if I am getting ignition voltage to the starter solenoid and I am not! I am only getting 4.5V with the key held in the start posit. I'm testing with the feed wire unplugged and would expect batter voltage. I'm testing using a paper clip as a probe.

So then I've checked the engine bay fuse box and with the ignition on I have battery voltage at each side of all the fuses.

I then checked each of the fuseable links on the front of that box and they are all good.

Took the black relay out and checked that and I have resistance between the two small pins. If I put 12V across those pins I get continuity across the two large pins.

So I check the dash fuse box and find a 5 amp blown fuse. The owners manual is fairly useless and does not give a fuse listing, other than a few other fuses. According to the diagram it is fuse 44 but I don't know what it is for.

Anyway I replaced it and with the ignition on or off I do not have battery voltage either side of that fuse. Every other fuse has been checked and has battery voltage each side of every fuse with the ignition on.

So firstly can anyone tell me what that fuse is for please?

Secondly I suppose the next obvious thing to try is to put a feed to the starter solenoid direct from the battery to see if the starter turns?

Some additional information just before it died the information screen threw up a few spurious messages. One of which was for low brake pads, but the sensors are bypassed so I know that's false. I have a feeling it is a bad joint or high resistance somewhere, which might have thrown the error messages.

If the starter turns when I "hot wire" it where do I go next?

Car's been out of use for a few weeks waiting for good enough weather to be able to have a crack at it and I need it back on the road.

 

[Westy1600]

You've crossed a lot of the list. Sorry, but the only thing I can think of is the earth strap.

 

[kratos]

a quick google got this info,,,,,,

fuse 44 , 5 amp is for ALARM

Fuse box Volkswagen Touran (fusesdiagram.com)

 

[Koicarpkeeper]

That's very useful.
Especially so because it shows there is a starter motor relay on the Type 2 relay board. I've got the Type 2 engine bay fuse box but will have to check against that diagram to identify the relay board. Will nip out later and take a look because it is easier to see in the dark with a torch.

 

[kratos]

maybe a suspect main ignition R1 relay.
easy to test relays with a 12v power source and a multimeter

 

[oberlisc]

Just a thought, have a look at the condition of the thick red cable and the thick black cable in photos 2 and 3, the black may go to the back of the Alternator, when my brother was having the same type of issue in his Ford Galaxy which had the VW 1.9 diesel engine, it turned out that Ford supplied the cabling in the 3 vehicle the VW Sharon and Seat Alhambra, with Ford it was under rated it was rated at 110amp, but if you had engine running , lights on, stereo, heater blower and so on it overheated the cable, that was the black cable running to the Alternator, it was easy enough to check the end of the cable wouldn't be shiny copper it was black and sooty.

After replacing the cable found that the battery had a dead cell, which would make the car act like it had a dead battery, jump start and the car would fire in to life.

 

[kratos]

when my bmw popped up several spurious messages on the idrive ( power steering ,abs.seat airbags and pretensioners )etc etc and needed a jump start , it was a knackered battery.i limped it along with overnight charges etc ,but it was shot, it had lasted 12 years tho

 

[Valer]

I thought i'd have a look in Haynes Pro to see if it shed any light but i needn't have bothered,
as expected it was as much use as a chocolate teapot,i'm glad i got it for free lol
I'd carry on as you are,pin the starter relay down and work from there,it may save having to crawl underneath the car.

 

[Koicarpkeeper]

I woke up stupidly early this morning after only a few hours sleep so I have been out and now have access to all the relays. Can just about get my big hands into them.

I'm wondering though if the car is immobilised because the alarm fuse had blown? No key symbol on the dash though.

Can't do much now cos I've got to earn my keep and Tuesday is shopping night.

Getting to the starter is easy enough but I don't think it is that, the car has only done 60,000 miles.

 

[Valer]

If it's a standard 4 pin relay you can check if it's getting a crank request which would rule out the immo if it is,
and try bridging the relay contacts to see if it cranks,
don't know why i'm telling you that though,i'm sure you're already aware of what to do

 

[Koicarpkeeper]

What's puzzling me at the moment is why there is no 12V supply to the fuse that blew? When I lock the car the red LED on the door flashes as it should to show the alarm is active.

 

[kratos]

Faulty relays that don't disengage circuits can drain batteries , keeping circuits live can create excessive currents and pop fuses.

For me I wouldn't think twice about throwing 15 quid at a brand new relay.

I'd be down the motor factors now

 

[Koicarpkeeper]

So would I but unfortunately I'm still a wage slave.
Your explanation does of course make perfect sense and would explain the battery draining.

One other thing it has done for ages is that the rear interior lights stay on while the engine is running, the fronts behave as they should. They all go off when I lock 🔐 the car and stay off.

 

[Koicarpkeeper]

OK some more investigation after managing to get access to the relays.

433 is the starter motor relay, which has 12V going to it and clicks nicely if I test it direct to the battery. It's a bit different because it has a secondary output terminal D which is directly linked to terminal 87 with the ignition off. So it looks like that relay also powers something else when it's powered up.

I popped the cover off it and inside is pristine with no signs of arcing or burning. Unfortunately it is the only relay like that so I can't swap it with another one.

So I tested the starter motor wiring again and something is not right. With the ignition turned on I get 7.3V at the solenoid connector with it unplugged. I would expect zero volts ⚡.
If I turn the key to the start position the voltage drops to 4.3V whereas I would expect battery voltage.

Now the other night I wasn't getting the 7.3V with ignition on, I was getting zero volts and all I've done is pull the relay out.

I really need a wiring diagram so I can see where it goes from the starter relay.

 

[TTT]

Touran 1.9 year unknown

 

[Koicarpkeeper]

2005 year. I think it's the 110 Bhp version.

Some more information - I briefly had battery voltage back at the alarm fuse but only on one side of it. Checked and it hasn't blown. Then I am back the same as yesterday with no voltage at the alarm fuse again.

Took relay 433 back out and checked the feed to the coil on pin 85 and it is only 11.2V so it is losing more than a volt somewhere. ⚡

 

[TTT]

I have the diagrams. But there are 7-8 engine codes for 1.9 and none 110 bhp. Which engine code is yours?

 

[Koicarpkeeper]

Does this help?

Looks like it is the 105 Bhp engine.

 

[TTT]

Yes, BKC, let me get something out of it.

 

[TTT]

Is this something you can work with?