Missing Engine Timing Fuses

[putin]

First post so be gentle with me. I've searched but can't find any info on this.

I recently bought a 97' 1.9 TDI Avant Quattro which is having trouble starting on cold mornings. The battery reports around 10v and the battery warning icon displays with a beep despite the battery having a good 13v charge when disconnected, then the car takes 2 or 3 attempts to get going.

I plugged it into VAG COM Lite and got a bunch of error codes, cleared them and 01265 (EGR Value) came back immediately.
I checked the connection on the pressure converter, which looks fine, then decided to check the fuses.

Turns out half my fuse slots are empty, all the engine timing fuses, 29, 32, 34, are missing.
Some I clearly don't need, no sunroof etc, but I guess the ABS fuse would be usefull

Apart from the cold start issue the engine appears to run well.

I'll be fitting the missing fuses as soon as I get a chance. I'm just wondering if the previous owner has done this on purpose to cover a serious issue.
Anyone seen this before?

 

[Arrkon]

I'll be fitting the missing fuses as soon as I get a chance. I'm just wondering if the previous owner has done this on purpose to cover a serious issue.
Anyone seen this before?

I wouldn't be the first time I've seen that trick...

However, those fuses are for the Engine management ECU and Sensors (one being the EGR, potentially creating the 01265 code for open circuit), best bet is replace them and see if the car runs better. if not, Report back, and someone will be able to help. Though something tells me you wont need all of them, as im pretty sure one feeds the ignition coils on a petrol variant.

 

[adamss24]

Look for terminals fitted to the fuse box, if no terminals then there's no need for a fuse as it's an open circuit ! I would check the starter and replace the battery with a known good one, sometimes old batteries don't have the cranking power needed to move the engine on a cold day !

 

[putin]

OK, thanks that's good advice.
I've checked and all slots with connections are filled so panic over. I feel rather foolish now.

Looking through the wiring diagrams in my Haynes manual I can see that Arrkon is right, all these engine timing fuses are only used on the petrol versions. The TDI engines use a fuse in the '3-point relay carrier'. I'm not sure where that is, I'm guessing it's in the engine bay ECU box, need to do some more googling.

The battery is a Unipart Calcium with a date number line marked 4-12. It looks pretty new so I guess that's April 2012 and the previous owner has replaced it recently. It's measuring 12.8v so I am loath to fork out for a new one until l I'm sure that is the problem. The local Unipart is open at the weekends so I might pop down and see if they can test it properly.

How do I go about checking the starter motor?

 

[Arrkon]

The TDI engines use a fuse in the '3-point relay carrier'. I'm not sure where that is, I'm guessing it's in the engine bay ECU box, need to do some more googling.

could be:

 

[Arrkon]

on a side note, IIRC the b5's have a "Load reduction relay", basically switches off heater/wipers/lights etc when you turn the key to allow more power for starting. could be an idea to check.

Test it by tuning wipers on full before starting engine, and they should stop for as long as you are cranking the car over, then start again once you release the key.

It lives here, number 213:

 

[putin]

Thanks for the photos, big help. I'll check the fuse this weekend.

In the meantime I did the wiper test, they stop OK so the relay must be good.

I've also made some extra checks on my battery prior to taking it for a test.

When I parked up last night I disconnected the battery negative lead and checked the voltage, it read 14.5v, so a good charge.
This morning, with temps around 6 degrees C, I checked the battery again. It had dropped to around 12.5, so still good.
I reconnected the negative and measured again. The voltage dropped to 11.9v.

I got in, put the keys in the ignition and turned on the electrics, now the dashboard voltmeter showed just over 10v.
I turned off the fan and the radio was already off.
When I try to start up the voltage drops to 8v while cranking, dash lights flicker, battery warning beeps, trip odometer resets etc, not good.

The funny thing is after each attempt the voltmeter creeps up a bit, after 3 or 4 tries it gets near 12v and the car starts.
This is what I get each morning, I haven't ever had to jump start it yet.

I have previously disconnected the coolant temp sensor and it does start much faster if I give the glow plugs a long preheat. The temp gauge shows sensible temps, around 80C when warm, and VAG COM does not list any errors on the sensor, only an intermittent fault after disconnecting. Checking that was actually what started me on the EGR Valve Pressure Sensor error.

I've also checked the current drain on the battery when the car is off. It's only drawing 0.02A which I believe is fine.

 

[putin]

---

So i spoke too soon about the car always starting. I was about to drive to ATS for at battery check and it failed on me. At least the car has a sense of humour.
The test centre said they need a good charge to properly test a battery and I've no jump leads right now (father in law has them) so I'll have to do that another day.

I checked out the ECU box fuses. They are all good so it looks like a new N18 pressure converter is on the cards.

After recharging the battery i did a couple more tests. It had a 13.5v charge but the dash only read 12.5. After a bit of fiddling around pulling fuses etc the dash read 10v and started sounding the low battery warning... but the multimeter reading across the battery while connected was still 13.5v.

Could a bad ground lead be causing this? Anything else I can check before giving up and taking it in to the garage?

Thanks.

 

[putin]

It's been a while but I thought I'd better close off this thread for the benefit of others.

I replaced by battery and the car has been fine for the last month. Always starts no matter what the weather and despite some long periods parked up over Christmas.

I was checking the option codes sticker in the boot and noticed it listed the stock battery as "Battery 380 A (80 Ah)"

The fitted battery was a 64Ah 640CCA. It's the cheapest Unipart do for the car but it should have been OK based on the CCA and was only a year old.
However I read there can be a little bit of marketing spin in CCA values so decided to get a new one with the correct Ah capacity.

Opted for a Varta Silver Dynamic 12V 85Ah.
It's the largest battery that will fit so I need get a one of the oversized battery clamps but it's doing the job brilliantly.

Thanks to everyone for the help.