MK5 GTI Steering Wheel Controls or Horn Not Working

[Omerta11]

Update - despite what I said, I was unable to do this over the weekend. As John Lennon once said, "life is what happens to you while you're busy making other plans". Long weekend coming up here in Adelaide, so I should be able to escape the wife and family for a few hours and give this the time it needs.

Ok, so I spent a few hours on it today. Checked all harnesses, and re-seated as many plugs as possible under the dash. No change. Still, the steering wheel buttons, nor the horn work.

The next step is to get a guy in to check the coding for me.

Unless anyone has any further suggestions, I'm gonna have to live with it for a while, or take it in for some (potentially expensive)exploratory work.

[Omerta11]

Ok, so I spent a few hours on it today. Checked all harnesses, and re-seated as many plugs as possible under the dash. No change. Still, the steering wheel buttons, nor the horn work.

The next step is to get a guy in to check the coding for me.

Unless anyone has any further suggestions, I'm gonna have to live with it for a while, or take it in for some (potentially expensive)exploratory work.

Had a guy come out today and check the coding. After clearing out the previous errors, he said that the steering wheel stalks are reporting errors, despite the fact that the stalks are fully functional. He reckons that the errors reported from there could possibly be affecting the issues I'm having with the steering wheel buttons and horn. He also said that the car is reporting that there is no passenger airbag installed!

I've had the car since new - I've done no mods to it at all. This is truly getting weird.

Said he got no codes response from the horn or the buttons on the steering wheel. He suggested that maybe the clock spring and/or steering control module I've had replaced are faulty, or are not plugged in properly. I'll have to check these (again) and see.

[Omerta11]

Had a guy come out today and check the coding. After clearing out the previous errors, he said that the steering wheel stalks are reporting errors, despite the fact that the stalks are fully functional. He reckons that the errors reported from there could possibly be affecting the issues I'm having with the steering wheel buttons and horn. He also said that the car is reporting that there is no passenger airbag installed!

I've had the car since new - I've done no mods to it at all. This is truly getting weird.

Said he got no codes response from the horn or the buttons on the steering wheel. He suggested that maybe the clock spring and/or steering control module I've had replaced are faulty, or are not plugged in properly. I'll have to check these (again) and see.

I ended up pulling apart my steering column this afternoon...

I discovered that the guys who installed the Steering Control Module did not plug it in properly - one of the plugs was loose, and its associated locking clip was not engaged. And, for some strange reason, they had also re-installed my old clock-spring (I had left it on the front passenger seat when I dropped it off for them to fit the Steering Control Module). I've paid good money for very poor service
So, after re-plugging in the Steering Control Module, and (re)installing the new clock-spring, I now have my steering wheel buttons back!

The only downside, is that the horn still doesn't work.

Almost there I guess - does anyone have any ideas what to do from here?

[vinnY]

weird, pretty sure the horn wires go through the clockspring too since the mechanism is along with the airbag
when my buttons went out, so did the horn(no errors for the airbag though, naturally jumped to the assumption that the clockspring has broken wires)
inspecting and reseating the cecm seemed to solve that

i'd actually initially replaced my clockspring too but they didn't solve anything, ended up reinstalling the original one in the end and haven't had any troubles with it

[Omerta11]

weird, pretty sure the horn wires go through the clockspring too since the mechanism is along with the airbag
when my buttons went out, so did the horn(no errors for the airbag though, naturally jumped to the assumption that the clockspring has broken wires)
inspecting and reseating the cecm seemed to solve that

i'd actually initially replaced my clockspring too but they didn't solve anything, ended up reinstalling the original one in the end and haven't had any troubles with it

It's weird indeed.

Latest is that we believe the issue lies with either the clock-spring or the horn switch. The horn relay works and all fuses are fine - we were able to beep the horn when the software system was plugged in, so we know the issue lies early in the chain.

I say the horn switch might be a possibility because when I took the airbag/horn off to start dismantling the steering column, I noticed that the wiring for the horn and airbag looked screwed up - I'm not convinced it's wired correctly. Considering the poor job the guys did fitting and testing the Steering Control Module, I'm wondering if they screwed around with this too.

I've been trying to find a wiring diagram for the horn/airbag online with not much success - I don't want to re-configure the wiring in case it makes matters worse. The Part Number for the airbag/horn assembly is: 1K0 880 201AH 1QB

The clock-spring is brand new, so it shouldn't be that. But I'm not ruling it out as it's been in and out of my car twice. It could have been damaged, or it was faulty to begin with.

Got my mate coming out on Monday to clear out all the error codes and to check/test the clock-spring and the horn switch. I'm hoping this will narrow it down further.

[Omerta11]

I’m happy to report it’s Finally Solved!!!

As I suspected, the wiring for the horn switch was wrong. As to why, I can only put it down to the guys that I got to install the Steering Control Module - they clearly had no clue what they were doing.

I analysed the wiring harness for the horn switch & airbag. Without a wiring diagram, it was hard to work out what was right and wrong. I looked online for a wiring diagram and couldn't find an exact match, but found some similar ones.

One wire looked to be plugged in the wrong connector lug based on its plug size and configuration, and another connector lug was bent out of shape. I fixed the bent lug, and looked closely at another lug on the opposite side of the unit where I suspected the misplaced wire should go - it was scored, so I made an educated determination that the wire in question had been plugged there previously. Plus, it looked like where the earth/ground circuit should be connected based on the similar wiring diagrams I was able to reference.
I took the plunge and wired it the way I thought it should be. Put it back in the car... and it all works!!!!

Car is back to normal - very happy, and satisfied I was able to work it out.

Totally furious at the guys that (incorrectly) installed the Steering Control Module...

Lucky for me, I had the time and (limited) expertise to work through the issues. Goes to show that when you want something done properly, you do it yourself - and with the help of this community!

[Transporter]

I see that you don’t need me anymore to come tomorrow.
But hey! Not that I’d want to blow my own trumpet here, but wasn’t it me, who told you that the mechanic who dismantled and installed the module most likely didn’t push the connectors back in properly?

I just didn’t want anyone to think, that it could be or was me who stuffed up!

[Omerta11]

I see that you don’t need me anymore to come tomorrow.
But hey! Not that I’d want to blow my own trumpet here, but wasn’t it me, who told you that the mechanic who dismantled and installed the module most likely didn’t push the connectors back in properly?

I just didn’t want anyone to think, that it could be or was me who stuffed up!

Definitely wasn’t you who stuffed up! And yes, you did say it was likely the SCM wasn’t installed properly. You helped me out heaps during this process - much appreciated.

Still want you to come out tmw - I still want to swap over the cluster as we discussed (if possible).

[Omerta11]

Just thought I'd do an update, purely for those of you out there who may have experienced similar issues...

A few days after I posted that the issue had been resolved, the problem came back - I lost the steering wheel buttons and horn functionality while doing a short drive across town. It stayed that way until about a week later, then they started working again for no reason. A quick switch-off and switch back on and it was all gone again. Frustrating...

Long story short for all of you, the one item that was never considered was the Steering Wheel Button Control Module that sits in the steering wheel itself. If you remove the airbag on your steering wheel, you will see ribbon cables coming from the left and right steering wheel buttons connecting to a small box at the base of the steering wheel.

I found a second-hand one from a wrecker and installed it - everything is working again.

Now, I'm not holding my breath just yet... when the issue was (supposedly) resolved a few weeks back, the issue returned after a few days - so here's hoping it will stay fixed.

Thanks to kamold for helping me out and suggesting that I look at the module.