Interior lights fault, and clock, and radio....GGGRRR!!

[aog]

Hi all!

Wondered if the groups experiance3 could help me out on some odd faults on other half 1997 300TDI Disco Auto.....

Firstly the interior lights don't work, when you open the doors or plip the cental locking. I have checked the switch on the door post, at least it stops the beeping when you close the door if the keys are in the ignition.

There seems to be 12V at the bulb contacts, though nothing happens, though the bulb does glow very faintly. It seems as there is power until you put a bulb in???

Whats all that about??

The rear light seems to be the same too. Though the glove box light is fine and works of the headlights when you open the glovebox as normal.

Also, the digital clock has gone odd too. It won't hold a time, it only works when you have the engine going it seems, it pretty most on at 1.00 all the time. Every time you get back in the car it's back to 1.00

Whats all that about??

Also radio packed in, though there does seem to be 12v, I have the original radion to try once I get the code.....

Coupled with the bloody thing not wanting to start in the morning!!!!

GGGRRR!!

HELP!!!

[muddymart]

well im sure ive been here with mine (6 days after purchase) i think the interior lights,radio etc...run off the same fuse, so check connection at the fuse box, and make sure everything is earthed,thats what i usually do, if i find the fuse holders are slack,bend them forward with some tweezers(womens tech dept) holds the fuse really tight !!
re: starting , i dunno always had diesel. try new plugs/oil/filter, i heard someone say press the gas pedal once to floor then release then start up.this could be an old wives tale.(having a new wife , :roll: we havent got to the tales yet)

[aog]

well im sure ive been here with mine (6 days after purchase) i think the interior lights,radio etc...run off the same fuse, so check connection at the fuse box, and make sure everything is earthed,thats what i usually do, if i find the fuse holders are slack,bend them forward with some tweezers(womens tech dept) holds the fuse really tight !!
re: starting , i dunno always had diesel. try new plugs/oil/filter, i heard someone say press the gas pedal once to floor then release then start up.this could be an old wives tale.(having a new wife , :roll: we havent got to the tales yet)

I think the fuses are ok, I do have 12V everywhere...... I am wondering if it's something to do with the courtesy light delay unit???

As for the press the pedal, according to the Haynes book, as the late models are all electronic pressing the throttle, turns them off IIRC!!!

I have some new glow plugs, but think I need a o ring for the crankcase breather, as I need to remove this to change one of the glow plugs, again, according to Haynes....

[Thrasher]

Sounds like a bad earth....

[muddymart]

sorry didnt read it as a tdi,silly me :? ,  i do 2 turns of the ignition,pre-heating the plugs twice,on the third i start it, does it great for me especially in this cold weather, ive only had my a week or so,drove it once,decided to get the timing belt changed,as i really didnt know what sort of history it's had,only by looking at the mileage.hopefully get it back tomorrow,then the fun starts,

[ChrisW]

It sounds like it could be the MFU (Multi-Function Unit - although a better name does spring to mind    :lol: )
The interior lights are not your conventional supply from the battery to the light and earthed through a door switch - everything wires back to the MFU and the MFU switches things on and off depending on what signals its getting.

Based on my experience with lights and things I'd say it could possibly be an earthing issue - there's a main earth adjacent to the main fusebox under the bonnet, behind the side kick panels in the front footwells and I think one in the rear somewhere...  :?

[beast5680]

mine had a start fault once turning over but not firing, i found one of the glow plugs was u/s, once i changed them no trouble at all starting.
re the lights fault check the light is earthing ok as one of the nuts that holds the unit in the roof is the earth as it screws thru the metal part of the lamp

[aog]

It sounds like it could be the MFU (Multi-Function Unit - although a better name does spring to mind    :lol: )
The interior lights are not your conventional supply from the battery to the light and earthed through a door switch - everything wires back to the MFU and the MFU switches things on and off depending on what signals its getting.

Based on my experience with lights and things I'd say it could possibly be an earthing issue - there's a main earth adjacent to the main fusebox under the bonnet, behind the side kick panels in the front footwells and I think one in the rear somewhere...  :?

Oh dear, don't like the sound of a MOFO ;-) Though it would explain why the bulbs are dim. Will have a look at the earths.

As for the starting, I am sure it's glow plugs, are they easy to change??? Doesn't look too involved I think, just not too sure if I need any washers or gaskets.....

[Damonski]

Is the battery in good condition?  My Mpi was struggling to start and run nicely until I popped a spanking shiney new Varta on it.

Never known the engine start so quickly now :)

[TUFFTEE]

If You have Fusible  Links under the Bonnet? I would Check them out as Well? :lol:

[Spooky]

All of the systems you describe are fed from the same fuse - Fuse 6 in No2 Satellite fuse box (attached to the bottom of the under-dash fuse panel), so I'd suggest checking here first.

The stray voltage you're seeing is probably being back-fed from the MFU ...

[Tyke]

The stray voltage you're seeing is probably being back-fed from the MFU ...

Possible - that said, I wouldn't overly rely on a simple voltage check, all it will do is confirm a voltage exists in the circuit. If it is a 'voltage leak' it may not possess sufficent current to illuminate your lamps but will still indicate a voltage exists ion the circuit.

First check, as most have suggested, would be to look at the relevant earths.

[aog]

All of the systems you describe are fed from the same fuse - Fuse 6 in No2 Satellite fuse box (attached to the bottom of the under-dash fuse panel), so I'd suggest checking here first.

The stray voltage you're seeing is probably being back-fed from the MFU ...

Hi All!!

Well it turned out that it was just this fuse that I had missed a 20A fuse, it's a aux fuse according to the manual, and I wonder if this had gone whilst we were towing, as I guess it would use this fuse maybe?????

Everything works fine now!!! :D

Can't work out why when the fuse is gone it gets some voltage and causes the radio to flash on and off??

Thanks for everyones help!!

[Wanderer]

Check your towing electrics. It may be that this fuse also does the aux wiring on the tow bar. Which may have overloaded it when you were towing.

[aog]

Check your towing electrics. It may be that this fuse also does the aux wiring on the tow bar. Which may have overloaded it when you were towing.

I see, was thinking this too..... IIRC I think I connected the grey wire on the towbar as usual, but not connected the battery in the van (I Forgot) Maybe the battery leads shorted and blow the fuse??? I am sure it wasn't turned on inside the van, maybe it was.

If the general consensus seems that this action would blow my fuse, I would be happy, at least I know that I can sort it. The electrics are not that old, only a matter of months, and were fitted by a specialist.

I know the lights work on the van as I check them, but thats not to say it did not short the charging system......