SKODA FABIA COMBI 1.2 HTP 2003

Power steering stops working when I go above maybe 85km/h or so, usually this is immediately after reaching this speed, and when the car reaches speeds below around 10km/h or stops, the power steering suddenly works again until again reaching the higher speeds.

When I go consistently above 110km/h the dashboard lights start flickering and turning off momentarily, maybe after 10 to 20 minutes, the parking brake red warning light will flash, followed by three beeps. If I continue driving at these higher speeds the ABS and parking brake red warning lights will continuously turn on and beep, and the speedometer and tachometer will turn off.

There is however no change to the car's on road behavior at all when these things happen (except the lack of power steering ofcourse), acceleration and braking works fine, in-fact when this started happening I was 100km's in a 1200km journey, so I did 1100km's on a highway without an issue and then some 300km's a day later.

Looking into it I think I might have an issue with "load sense (dfm) wire" or the alternator, does that sound about correct?

I have seen some posts on this forum, but can't seem to find any diagram or guide to be able to find the DFM wire, could anyone help here? 

Have you checked your batteries' ground connection (between battery and front wing area)? Make sure it's clean. That was the issue with mine, but also check this DFM wire too - I can't provide help there, sorry. I hope you can get this sorted!  

@AnnoyingPentium Thank you for the reply,  how would I use a multi-meter to check the ground connection?  And cleaning means, sanding, or? 

7 minutes ago, Robstelly said:

how would I use a multi-meter to check the ground connection? 

 

I didn't check mine with a multi-meter so I can't help there sadly, but possibly on a continuity setting?

 

8 minutes ago, Robstelly said:

And cleaning means, sanding, or? 

 

Yes, I used a nail file with mine on the end that connects to the body.

Strange one.

Maybe grab one of those little LED voltmeters that plug into your lighter socket so you can see what the charging system is doing at various rpms.

 

On your car I think the connector pair with DFM and alternator excitation wire will be the top, black pair, seen here just below the starter motor.  

 

 

@Wino

Oh, so the exciter cable and the DFM cable, are connected to each other?  Would I be looking for visible tears and the like in the entire length of the cable (highlighted red) or only the (highlighted green) part? 

As for the voltmeter, unfortunately the cigarette lighter  doesn't work at all in my car, probably a completely unrelated issue as it's all ****ed ****ed up looking.  I've bought a multi-meter and will try to test everything on Saturday. Then I'll try to get to a place where I can lift up the car and inspect all the cables. 

They pass through the same (2-way) connector pair on their way to the alternator, though separate wires all the way. Breakages are usually easily seen near that connector pair.

 

Check fuses for the ciggy lighter.

 

Does the battery light come on with ignition, before starting engine? That's a giveaway for a broken (blue) exciter wire if it doesn't. 

@Wino The battery light doesn't come on, actually. I pretty much ruled out the exciter wire but then I noticed that the battery light doesn't come on so I guess it's broken also... It couldn't just be the exciter wire alone causing all of this, right?

I'm not sure, but mending broken connections is rarely a bad thing.

 

It would be really helpful to be able to see if the system voltage is doing anything mad at the times you're seeing the faults, so see if you can resurrect the lighter socket after wiring repair(s).

Yeah, thank you a lot. I'll look into how to repair the lighter socket. Tbh this is my first car and my first time messing with cars so it's just a little overwhelming, still have to get all the tools and sort out where I'll even repair it (and I assume I'll need to lift it too.)

1 hour ago, Robstelly said:

It couldn't just be the exciter wire alone causing all of this, right?

Well, maybe. I had a stuck (open) sprague clutch on the alternator, which threw every warning light except the battery light and oil light, and turned off the radio and the ventilation fan, and recorded about 30 fault codes according to my garage. None of this recurred when the clutch was replaced.

12 minutes ago, KenONeill said:

Well, maybe. I had a stuck (open) sprague clutch on the alternator, which threw every warning light except the battery light and oil light, and turned off the radio and the ventilation fan, and recorded about 30 fault codes according to my garage. None of this recurred when the clutch was replaced.

How did you diagnose it?

14 minutes ago, Robstelly said:

How did you diagnose it?

I realised there was something electrical wrong when I got the light show and the radio turned off and wouldn't go back on. I took it to the garage who said "the alternator isn't turning" and then "the clutch is stuck open". I'd only had the car 3 weeks, so Arnold Shark got the bill for diagnosis, parts and fitting.

@Robstelly I doubt your car has a freewheel pulley on its alternator.  Take and post a photo end-on if you're not sure what to look for.

@Wino Tried using a phone to see underneath but wasn't really able to, so I'll need to pay for it to be lifted and look at the cables then.  I took a picture of the alternator but not from the cable side so I guess that's entirely unhelpful. 

I am just scared that even if I lift the car, I won't really be able to to tell what a damaged cable looks like, I've looked around and the post that people point to https://www.seatcupra.net/forums/threads/how-to-fix-broken-load-signal-cable-from-alternator.209472/ , no longer has the pictures. 

For fixing it, I assume I can just follow any cable fixing tutorial and use a solder to connect the cables together, however, as I am reading this forum I realize the reason the cable breaks to begin with is that it's too short, so will I even be able to rejoin it, is there some way to lengthen it? 

Finally (and sorry for asking so much) I've just gotten my multi-meter and tested the battery voltage, when the engine is on, it's actually perfect right around 14.25, so the alternator seems to be doing it's job.... Is this normal even when the sense load & exciter cables are broken? 

1 hour ago, Robstelly said:

I took a picture of the alternator but not from the cable side so I guess that's entirely unhelpful. 

Depends, it may show the presence or absence of a freewheel pulley, depending on the angle you've caught.  Cable breakages are almost always at the area highlighted in my photos above though, which you may well be able to see looking down from above, I'll link you to a thread with lots of photos.

Page one, two different cars, red one most like yours. load signal alternator cable - Skoda Fabia Mk I - BRISKODA

 

The alternators tend to start up without the blue wire, but only once a certain rpm is exceeded, this mostly causes problems with diesel variants, where some journeys may never surpass the necessary rpm, so the alternator never starts charging.

 

The cable damage is usually very obvious, like dead-ends of wires that go nowhere, because they've completely snapped.  You can add in lengths of any old cable to bypass the connector pair if there's not enough available to reach by whatever repair method you choose.  

 

Really not sure of the relevance level, to be completely honest.

Edited 17 October, 20214 yr by Wino

This is the view you can get from above on a 1.2/12V, with just the engine cover removed, I think.  Just visible beyond the starter motor:

 

 

2 hours ago, Robstelly said:

Is this normal even when the sense load & exciter cables are broken? 

Ah, should add that one or both of them do sometimes pull off the alternator terminals without the cable being broken.

@Wino I found a place which lets me use a lift for 12 per hour, lifted the car up and looked for a broken cable everywhere but couldn't find it.  So I took a picture of every cable I could find... and also the alternator.  I looked pretty clueless so some guy came up to me and also tried having a look then told me he had a similar issue caused by a blown out fuse. But honestly I am not even sure whether I was looking at the correct cable? Turns out I am pretty bad at this and everything looks the same to me 😭 

Thank you for your continuous support... do you see anything in the pictures? I have more & also took a video.

Third and last photos have captured the lowest couple of connector pairs on the rusty metal bracket where the alternator connections are, but you can't see the top two 2-way connections, the brown and black ones visible in photos of the red Fabia in the thread I linked you to in a post above, on Sunday evening. 

Edited 20 October, 20214 yr by Wino

The chances of finding this fault with your eyes are slim at best, wires often break internally.

 

You should take it to a specialist auto electrician to be diagnosed, garages are usually very bad at electrics.

The alternator pulley is shown not to be the type with freewheel clutch, so that won't be broken!

Can you link to the video? 

Edited 20 October, 20214 yr by Wino

@sepulchrave I am in no position to argue but it seems that everyone who has an issue with the sense/exciter cable has a clear break and fixed it themselves, at least on this forum there are a million threads about it already. 

@Wino Here's the vid, but I am not sure whether it ever goes over the cable you seem to talk about. 
 

 

11 hours ago, Robstelly said:

@sepulchrave I am in no position to argue but it seems that everyone who has an issue with the sense/exciter cable has a clear break and fixed it themselves, at least on this forum there are a million threads about it already. 

Also @Wino The reason I mentioned the alternator clutch is that it is a known source of failure when fitted, and easily checked either way.

 

Similarly, it is not unusual for a control cable to pull off the alternator connector, and that's also easy to check. That said, since said cables are maybe 2cm shorter than would be ideal, if the easy visual checks (done) don't show a failure, you need to move on to continuity checking wiring, but again starting with the control cables.