DIS red herring?

Malcyb

Member
Had a strange thing happen yesterday. While driving through the rain, DIS emitted a loud beep (first time I’d heard this so it startled me) and the yellow warning symbol signifying “bulb failure, dipped headlights or rear lights” appeared. Think it happened about the same time as I put my foot on the brake, but I didn’t have lights on at the time. A minute or 2 later it happened again, though from recollection not when I was braking. At the time I thought it might be a warning for brake light failure however after checking the manual I realised that was a different symbol. Anyway, I checked headlights (full beam and dipped), rear lights and brake lights and they were all ok. Today the warning hasn’t recurred. Has anyone any idea what’s happened here, should I be concerned? Seems like DIS is reporting fake news... and anyway, the manual says “this function is only checked by the auto check control when the lights are on”. Which they weren’t.
 

timmus

A2OC Donor
Hi Malcyb,

Is the car's DIS fitted from factory or retrofitted, please?

Cheers,

Tom
 

audifan

A2OC Donor
Water in the rear lights? Check battery compartment for water. Bulb failure module?
 
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timmus

A2OC Donor
From the factory... i remember it from when I drove it back in 05 when my dad owned it...
OK, thank you.

@audifan's suggestion regarding water ingress is definitely worth investigating. Assuming all is well with the lights themselves, then my suspicion is that the 393 relay is faulty. The 393 can be found directly above the fuse board. The under-dash trim will need to be dropped down in order to access it.
@A2Steve will almost certainly have a replacement.

Cheers,

Tom
 

Malcyb

Member
There’s definitely no sign of water ingress in the battery compartment and I unclipped the bulb housings for the rear lights, they looked fine to my untrained eye. I might wait to see if it recurs before doing anything with the 393 relay - would that be a simple job for a novice?
 

2work

A2OC Donor
I have a 393 relay here if you want to give it a try.

Just removed it from the car:

image.jpg

image.jpg

Kind regards,

Tom
 

Malcyb

Member
Just a thought - you didn’t mention the headlights. I noticed the other day when replacing my offside indicator bulb that somebody’s bodged the connector on the headlight and it’s now just hanging off, not attached to the headlamp housing at all....
A35819F8-0CAD-4D64-BF89-4E7DDFDCED0B.jpeg

Also, is there meant to be rubber trim all the way round the headlight? It’s missing at the bottom on mine, so there’s a sizeable gap between the headlight and bumper.
9A68A98C-26AA-4666-B093-65EAD58CADDA.jpeg

So I wondered if this could have led to water ingress getting at the connector. Not that I could see any obvious sign of that.
 

2work

A2OC Donor
@Malcyb,

The 393 relay is as @timmus said just above the fuse box, to the left of the 370 relay:
7AE11DBF-91A7-4F8E-A250-AE376E0BB12E.jpeg

Here it is already boxed up ready for posting this evening if you want:
image.jpg

Not sure on price so £12 delivered the fastest possible way I can starting this evening when I pop out for essentials.

Kind regards,

Tom
 

Malcyb

Member
@2work thanks so much for your help. However given this was a one-off yesterday and hasn’t recurred today I’ve no way of being certain that this is the culprit at the moment. So I might monitor it for a little while and see if the fault recurs. If you could hang onto it for a little while that would be great, but if someone else wants it in the meantime that would be ok.
 

2work

A2OC Donor
@2work thanks so much for your help. However given this was a one-off yesterday and hasn’t recurred today I’ve no way of being certain that this is the culprit at the moment. So I might monitor it for a little while and see if the fault recurs. If you could hang onto it for a little while that would be great, but if someone else wants it in the meantime that would be ok.
I’ll go and refit it into the car so it’s totally safe. It’ll be here when you might need it.

Kind regards,

Tom
 

audifan

A2OC Donor
DIS is only a display so something has sent a signal to it. False signal due to damp, or perhaps a bulb was loose but has reseated correctly. Standard bulbs or uprated / led?
 

Malcyb

Member
They’re standard bulbs. Damp might be relevant as she’s rarely been driven in the rain in the few months she’s been in my possession. These intermittent faults are the worst, can be so difficult to isolate the cause and hence know if you’ve fixed it. Hence monitoring it for a little while seems sensible.
 

audifan

A2OC Donor
Do you have condensation in your headlights? Contact corrosion and wire corrosion are the A2s weak points. Also chance as the car has not been used much the battery was low and had a surge from the alternator fooling the bulb sensing.
 

Malcyb

Member
Do you have condensation in your headlights? Contact corrosion and wire corrosion are the A2s weak points.
None that I can see, however I did mention further up the thread a concern over a rather flaky plug on one of them. And due to this the headlamp unit is open at the back where the socket should be which I guess would make it a bit of a target for damp inside.
 

Malcyb

Member
I tried reattaching it when I had the headlight out to replace the indicator bulb the other day, it didn’t want to know and there was no way I could extract the plug from the socket, I read the advice on the forum about it and found a couple of YouTube videos but couldn’t get the clip to budge. Looks like someone else tried and failed before which is why it looks like a dog’s been chewing it as you can see in the photo.
 

audifan

A2OC Donor
It only fits in one way round, perhaps you had it upside down. The plug can be a pain to remove, I put a small screwdriver into the release lever to lift the tang over the barb. While holding in the screwdriver I use a large flat bladed one on the long edge next to where the release is alternating on either side until it starts to come off. Once over the barb it is just the internal rubber seal that is holding it together. A lage flat blade screwdriver on both sides now usually pops it off.
 

Malcyb

Member
Thanks... I’m sure I was putting it back the right way, mirror image of the near side. I tried pretty much what you’re suggesting regarding lifting the catch, though not with multiple screwdrivers... I’ll give it another try tomorrow perhaps.
 
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