Reverse switch faulty?

[DarrenG]

Hello everyone,

My reversing sensor operates randomly while in forward gears and neutral, also the rear wiper also runs on intermittent when front wipers are on even if the stalk switch is in the off position, thirdly on the digital display the current gear number goes on and off,

My gut feeling is that the reverse switch on the gearbox is faulty, has anyone had this happen to them and what did the fault turn out to be?

Thank you in advance.

[sepulchrave]

I think you're right, test the wiring to the switch first, then the reverse switch itself.

[Thud]

Hi, I've had a very similar issue with my 1.9tdi Roomster and am wondering how you get to the reverse switch and wiring. Is it from underneath the car or what? Any insights?

Did you get your problem fixed?

 

Cheers 

[KeithCheetham]

15 hours ago, Thud said:

Hi, I've had a very similar issue with my 1.9tdi Roomster and am wondering how you get to the reverse switch and wiring. Is it from underneath the car or what? Any insights?

Did you get your problem fixed?

 

Cheers 

I would suggest looking at the following link showing item 17 which is probably the reverse switch in 2 possible positions. Depending on the actual issue, if it is only the reverse lights do not work, on mine I pulled the plug and used a paper clip in the wiring loom plug which operated the reversing lights with the ignition on. Leaving the plug disconnected temporarily while driving would test if other issues present.

Switches and senders on engine and gearbox Roomster (RO) 2008 year Skoda EUROPA 919040 (7zap.com)

Edited 17 December, 2023 by KeithCheetham

[Thud]

Hi, thanks for the link. I'm still  going to have to hunt for access to the switch and its wiring. The problems I'm having at the moment may be coming from a faulty/wrong brake pedal switch. When I get round to replacing it, I may well end up having to at least test the reverse light switch. See my thread 'Haunted Roomster' for further info.

Cheers

[DarrenG]

Firstly I apologise for not getting back sooner.

Before disconnection of the reverse light switch ( waiting for a dry day) I had further issues with the battery warning light coming on despite the voltmeter I have fitted showing no issues.

Once the switch was disconnected all faults have cleared, I am currently looking for a replacement switch at a reasonable price.

[Thud]

@DarrenG

 

https://www.skoda-parts.com/catalog/roomster/spare-parts/electrical-equipment/sensors/reverse-gear-sensor-540.html

 

Tried this link?

[SJFISHER67]

I changed the reverse light switch on my Fabia earlier in the year. It was tough to remove - I removed mine to top up the gearbox oil - upon refitting, due to the old threadlock stuff on the existing switch, it went in so far and sheared clean off! In a rage i stabbed a screwdriver into the remains of it and wound it out.

 

Now one fitted (cost about £30) from main dealer. went in like a dream, I accessed mine from the top, need a decent deep socket and take your time. Oh and be a bit of a contortionist!

[Thud]

Thanks for the insight, @SJFISHER67 just hoping for a dry spell to get out and have a look, do some yoga in prep for the contorionism 😉

[sepulchrave]

41 minutes ago, Thud said:

...hoping for a dry spell to get out and have a look 😉

 

Dry spell 😂

[GrahamM]

On 29/12/2023 at 11:31, SJFISHER67 said:

I changed the reverse light switch on my Fabia earlier in the year. It was tough to remove - I removed mine to top up the gearbox oil - upon refitting, due to the old threadlock stuff on the existing switch, it went in so far and sheared clean off! In a rage i stabbed a screwdriver into the remains of it and wound it out.

 

Now one fitted (cost about £30) from main dealer. went in like a dream, I accessed mine from the top, need a decent deep socket and take your time. Oh and be a bit of a contortionist!

I'm not getting the reversing light coming on when I select reverse gear on my Fabia Mark 2 HTP.

I've checked the bulb and the fuse and both are OK, so I think it has to be the switch.

Do you have any helpful advice on how to replace it (for a start, where do I actually find it! 🙃 )

[Breezy_Pete]

Wiring breakage adjacent to the connector plug is another strong possibility @GrahamM.

 

Lowish on front face of gearbox. 

[Breezy_Pete]

Red arrow:

 

[GrahamM]

2 hours ago, Breezy_Pete said:

Red arrow:

Thanks, I'll have to find somewhere off the street so I can take a look.

[KeithCheetham]

Unplug and then us a paperclip in the socket attached to the car wiring to bridge the 2 terminals, turn the ignition on and look if the reverse light is on. If you have the use of a multimeter it is possible to check for continuity across the wiring tabs in the switch when reverse is selected.

[Thud]

Hi everyone, does the pic above apply to a Roomster 1.9 tdi manual gearbox by any chance? Still have on-going electrical gremlins, but getting there.

 

Cheers 

[Breezy_Pete]

Unlikely, PM me your VIN if you'd like me to see if I can find stuff applicable to your gearbox.

 

[Thud]

PM on the way😀

[Thud]

Thanks to all, and a special mention to Breezy_Pete.👍

i don't need to find the reverse light switch now.

I tracked down the source of my reverse light/ brake light issue this afternoon  After removing the rear left boot panel I noticed that two wires from the rear light cluster loom had become trapped, chafed and shorted together.  The rerverse lamp and brake lamp wires, TaaDaa!

Trapped between the aux power outlet and the car frame, you can see the witness marks in the pic.

All sorted now so my brake lights and reverse lights and functions are now working and independent of each other. Thanks again for all your help and time.

On now to the next gremlin.

[GrahamM]

I've finally managed to find the gearbox reversing light switch and the problem, as you can see, there's a broken wire. (Great bit of design, Skoda, putting a thin piece of wire like that in a place where there's going to be a lot of stress and vibration... 🙄 )

 

Now the idea of trying to get a soldering iron down into there to fix it does not appeal but I'm not sure what else is feasible.

 

I could (possibly) get the connector off the switch, I think there's a catch I'd have to push down which is, of course, out of sight on the underside (another great bit of design!), however there's not much wire to strip back if I were to try to crimp a connector on to it.

 

Also I'd probably have to unwrap some of the covering to get to the rest of the wire on the loom side for the other half of the connector which is going to be fiddly.

 

If anyone else has had a problem like this, I'd welcome suggestions on the best way to proceed from here.

 

[Thud]

Hiya, have you seen this;

https://www.ebay.co.uk/itm/323974769047?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=4AXrxQfvTFi&sssrc=4429486&ssuid=akn2d3NASFC&var=&widget_ver=artemis&media=COPY.

 

There are loads of those  wired plugs available online, just check the numbers before ordering. If you can get the existing plug off the switch, yes it's fiddly, you're better able to strip back the loom enough to give you enough of the existing wiring to work with. Splicing your new wire on shoul prove easier. Soldering, crimp connections etc will be easier now. Don't worry about the colours on the new plug and tails, so long as the plug fits and there's two wires, you're good to go. If I remember correctly the wires going to the switch are coloured black/white and black/blue.

Looking at your pic above, this would indeed be the case.

Not too much loom chopping required at all.

Cheers

[GrahamM]

1 hour ago, Thud said:

Hiya, have you seen this;

Ah, now that looks perfect for the job!

 

I certainly didn't fancy trying to crimp a connector onto about half an inch of wire, but there appears to be plenty of spare lead going to the red plug on the left.

 

I'll have to try to get the connector off tomorrow to find the serial number and then pick one up off eBay.

 

Thanks very much for the help 🙂

[Thud]

You're welcome, no worries, let us know how you get on. I don't see why you'd need to do anything to the red plug on the left you mentioned, but that's only my guess. Once you start peeling off the loom insulation you'll get a clearer idea. If you do, could you please post a picture? Just for curiosity's sake and future reference. This seems to be a common fault.😀

Cheers

[J.R.]

Even easier perhaps is to buy an assortment of wired male and female connector pins and a set of depinning tools and then you will also be set up for any future requirements.

 

If only one wire is broken why replace the plug and both terminals? OK I can answer my own question, if one wire is broken the other may be on its way.

[GrahamM]

3 hours ago, J.R. said:

If only one wire is broken why replace the plug and both terminals? OK I can answer my own question, if one wire is broken the other may be on its way.

Yes, that was my thought.

 

Far better to replace the connector with a new unit and crimp on a couple of spade terminals than risk fixing just one side, only to find the other side or the OEM connector fails a little further down the line...