[Bob.W]

Hello Everyone,

In short, fully functional JUL17 PD, no physical damage, always garaged etc - driving into down yesterday in dry weather and with no seeming reason suddenly the display shows 'Check AEB system' error/warning msg. Multiple other icons also being lit up in amber.

Vehicle continues to drive normally - but becomes evident that multiple functions as lit up are 'disabled' i.e 'Autohold' lit up, tested and not working, same with cruise control - so assume likely the same with the other icons in amber (ABS,  stability control etc).

Checked online first thing to try was cleaning front/dash camera area - this did nothing. Appears fine, slight dust in camera lens area but within normal expected levels.

The front logo badge, that the front radar detector is behind is clean. Cleaned again, no change.

Disconnected battery for several hours, touching pos & neg connectors and leaving this way for an hour (was meant to possibly clear the error msg). Did nothing.

Wondered if folks had any ideas?  As feel I'm heading for what I dread, having to go to the local Hyundai dealership! 

Only other thing I can think of is maybe removing plastic guard below or above engine to get access to the radar detector thats mounted on the frontal collision beam behind the grille - perhaps it's dirty etc?

There's been nothing new installed or messed with on the car for many, many months - so I don't think it's been inadvertantly affected by anything else i.e installing dashcam etc.

Any thoughts or feedback welcomed - thank you in advance for your assistance.

[Aye30]

Hi, Test battery , if that is good look at brake fluid level. With so many things coming on at once, it is usually one common item that has many linked modules. A bad battery throws a lot of unconnected modules into panic mode, likewise one issue with the brakes can turn off a lot of connected systems. If the faults are not clearing after disconnecting the battery, it could be a sensor reporting back before the engine even starts, that all connected systems will not operate, due to a fault condition. I hope it is not your ABS unit.

[Bob.W]

Test battery

@Aye30 much thanks for the reply & suggestions.  Battery is definitely fine, under 12mths old, top of the range Century model thats rated above OEM CCA's & I even top it up atleast monthly with a multistage charger. Hasn't shown any signs of the battery being a prob e.g starting.

if that is good look at brake fluid level

Brake fluid level is fine, drained & replaced it around 18mths ago, just checked and it's at its max level, still looking that nice light colour you want.

likewise one issue with the brakes can turn off a lot of connected systems

Brakes seem good condition, need to replace the front pads this year but no hard braking events in recent memory that might have contributed.

If the faults are not clearing after disconnecting the battery, it could be a sensor reporting back before the engine even starts, that all connected systems will not operate, due to a fault condition.

This is kind of what I suspect/hope but not sure how to alleviate myself - Hyundai make it that you cannot even clear or check faults via their tricky internal ECU reading system.

I hope it is not your ABS unit.

Hmmm me too - think it's activated perhaps 3 times ever! Car is outside warranty, wonder if I have a statutory warranty issue if it's faulty?  As you'd not expect a unit to fault on a 7yr old, 80,xxxkm car. But no need to worry about what may not be the case.

Hmmm bugger seems I just have to book in via dealer and hope for best? Is not even like an indy mechanic can really look at issue as it's all ECU stuff, right?

[Bob.W]

I wonder if hitting any of the wheel ABS sensors or the front radar sensor with some compressed air to try and remove any issues might be worthwhile?

As it's only amber it means somethings not right, but it's not disasterous - but kind of sucks that everything from autohold to cruise control to AES is disabled. Hard to know where to start diagnosing it - think I am due to rotate the tyres soon, so maybe eyeball anything around the brake area that might look odd?

I think the ABS sensor is in a spot thats hard to access or see near the rotor?

Is worth noting, have not had any weird noises, behaviour etc from car since these error warnings popped up - nor anyting I can pinpoint as possible cause e.g hit a HUGE pothole and new it was bad right away.

[Aye30]

This is going to sound weird, are all the rear brake lights working? Way back in the 2010 models they had a brake switch recall, the switch has two circuits which verify each other, and the location of the brake pedal. The recall was because one side of the switch would fail, and the brake pedal location could not be determined by the computer. It turned off features connected to the braking system like esp and cruise control. From what I can work out with our 2010, if both lower bulbs go out the system turns off CC and ESP, and if the switch goes bad the center stop lamp can be delayed or not come on, which also turns off CC and ESP.   A good diagnostic code scan may be required, I don't know if a generic code scanner will read all the codes. My Elm based obd2 wont read ABS codes.

[Bob.W]

This is going to sound weird, are all the rear brake lights working?

Hi @Aye30 appreciate the reply and idea - sorry for the slow reply, was wrangling a lawn mower all weekend - the lawnmower won!

Just went and checked and yes all brake lights are working, did indicators as well - no issues.

Good idea and rationale though. Much thanks, still not sure what the issue could be.

[Gazza-75]

I've got the exact same issue as @Bob.W that started a few days ago just out of the blue.

Troubleshooting I've taken so far:
1. Checked and cleaned Radar and Camera - No issues or dirt found.
2. Checked all other sensors around the car and no issues found.
3. Attached an EBD scanner which came back with no fault codes whatsoever.
4. Disconnected the battery for a few hours - No change.

Other things I have noticed which keep happening intermittently:
- Radio keeps switching between the radio and media (USB music) or otherwise switches off altogether.
- Seatbelt warning lights only work intermittently.
- Electronic Power Steering (EPS) light has come on a couple of times.
- Front map lights are extremely hot to the point that it burnt my hand.
- Very poor fuel consumption which is currently over 11l/100KM in the last 50km's and I usually average around 8 due to driving shorter distances.

I also am not looking forward to having to visit my dealer to investigate as they have been pretty poor in the past in diagnosing my previous issues (lack of power, shuddering, etc), so was hoping there would be some insight in this thread.

Cheers guys.

[Bob.W]

I've got the exact same issue as @Bob.W that started a few days ago just out of the blue.

Gazza, ah that sucks sorry to hear you have it as well.  FWIW great work on your efforts to diagnose it, not sure you could have done much more - is a bummer that Hyundai decided to make their GDS system such a 'closed shop' system - nice for their dealers but bastardry for customers.

I'll also note I've not had any of your other mentioned issues/quirks. Don't use the radio a lot, no issues with the seatbelt warning signs, EPS warning has not been coming up at all, no issues with map lights (thats a very odd one!) and fuel consumption has been as per long term averages.

I think I might have to book in with the dealer as can't imagine it's going to clear itself up and is too risky driving a car without ABS, ESP etc - and once on highway major PITA not having cruise control.

[Gazza-75]

Agreed @Bob.W , I'll also probably have to bite the bullet and take mine into Hyundai as well. My own mechanic is good but this would need Hyundai's own 'senior' mechanics to sort this.
Will post updates here if that's OK.

[Vinu7172]

Hey y'all,

I've got a 2018 PD which did the exact same thing today. AEB warning, cruise control not working, auto hold etc. Additionally it doesnt detect my phone anymore either..

It's the factory battery so not sure whether it's time for a replacement. May need to take it to the dealer from the sounds of it though.

[The Gonz]

When I hear of so many things going wrong at once, I tend to think voltage. However, if this has been definitely eliminated, you'd be onto BCM or connections. My 2c

[Gazza-75]

BCM sounds interesting @The Gonz . I've had 'electrical' issues since owning my car, especially the cabin lights flickering/pulsing. Hyundai has not found any issues with the car other than a failing battery a couple of years ago which I immediately changed, but the issues persist.

Is it possible to 'reset' the BCM module perhaps?

[Shambles]

Is it possible to 'reset' the BCM module perhaps?

A BCM reset is done electrically - you simply disconnect a battery terminal for 30 mins then reconnect.

[Gazza-75]

@Shambles I've done that a couple of times already and made no difference.

I thought the issue went away over the weekend as it was fine for one of my excursions for about 30 minutes, but then my wife went to the shops in it and it was back again.

[Bob.W]

Hey y'all,

I've got a 2018 PD which did the exact same thing today. AEB warning, cruise control not working, auto hold etc. Additionally it doesnt detect my phone anymore either..

It's the factory battery so not sure whether it's time for a replacement. May need to take it to the dealer from the sounds of it though.

Wow another person with the issue!   Very surprising as it's not like we have a huge membership here - so 3 pretty similar ones in a week or so is very surprising.

Yeah I'm 99.9% certain mine has nothing to do with the battery - no idea if that might be a factor for you - always IMHO a good idea to go to somewhere like SCA or Repco who has a capacitance tester, that will advise how good the current state of your battery s to when it was brand new - batteries are notorious for appearing good on the voltage front but their capacity is completely shot.

But that is a separate issue to the main problems you, and I currently have.

Will be fascinating to hear what folks are advised - seems very odd a bunch of us in a small community all have them at once.  Do please keep us posted - trying to find the time to get mine dropped in to the local dealer to diagnose.

[Bob.W]

No one's diagnosed their's yet?   I'm waiting for pay day to book in - pita not having ABS etc with all the wet weather.

[Gazza-75]

Sorry @Bob.W , I'm in the same boat, plus I'm away camping this weekend. Hoping to book it in sometime next week.

[Gazza-75]

No one's diagnosed their's yet?   I'm waiting for pay day to book in - pita not having ABS etc with all the wet weather.

Hi @Bob.W , I've done some more digging on the internet and for the most part, the issue seems very likely to be the radar going out of alignment. I am in the process of removing my bumper to check out the radar and bracket but may take a day or two as I'm doing it during coffee and lunch breaks.

Will post updates on what I find.

[Bob.W]

Hi @Bob.W , I've done some more digging on the internet and for the most part, the issue seems very likely to be the radar going out of alignment. I am in the process of removing my bumper to check out the radar and bracket but may take a day or two as I'm doing it during coffee and lunch breaks.

Hmmm thats interesting.  Not sure how the radar module, which IIRC is bolted to the front collision/torsion bar, would go out of alignment?  Its behind the grille, badge etc and you'd think it'd take a fair old whack to hit it hard enough to twist & unalign it.

I know I've certainly not had any frontal impacts of any sort recently that could account for such a movement - but I will be interested to see what you find out.  Thank you for posting up your info & findings.

[Gazza-75]

UPDATE:
So, it's easier than I thought to remove the front bumper. I have now done the following but the issue remains:

1. Inspected the radar unit and no damage or shift to its original position as far as I can tell.
2. Removed, inspected, and then re-attached the wiring harness from end to end (4 connectors all up). No damage or broken wires. I will do a continuity test on the wiring when I have more time.
* The wiring goes to 2 separate units/sensors which I'm not sure of their function. I have attached pictures.
3. Cleaned the radar which wasn't really dirty anyway but the car still display the AEB error.

I thought I'd disconnect the radar and then the car only complained about the cruise control systems, which leads me to believe the radar unit is faulty/dead. Not sure how I can test this without stripping someone else's car and swapping the unit out.

Still a bit reluctant to go to Hyundai as I've heard that radar unit is thousands.

[Bob.W]

@Gazza-75
Terrific effort & write up, alas the beat goes on.

Lets ASSUME it is a faulty radar module, I would think it's plausable that statutory warranty would apply to it, even though the car is no longer under factory warranty any longer.  Statutory warranty in simple terms states that its reasonble to expect that the item would not have failed given the period of time & cost of the item.

I don't think a radar module should have failed after 7yrs.  Its not a consumable part.

Anyway we don't know if it's failed yet - and is an inexact area but I don't think it's certain you'd be liable for the cost.

[Vinu7172]

No update from me. There's a service coming up in 2 months so I might just leave it for then, hopefully the car doesn't have any lasting impact from this..

[Lorian]

Given it has widespread symptoms I'd think it's not likely to be the radar unit.

Not 100% sure where it will be but there should be an earth strap to the body somewhere behind the battery box. Worth a  clean and tighten.

If it's not that given the range of the systems affected I'd be checking the wheel speed sensors and rings.

A proper (Hyundai or more comprehensive 3rd part) diagnostic check should find the codes where the cheaper code readers don't query aeb/abs/BCD systems.

[Gazza-75]

Thanks for the insight @Lorian.

I've checked the wiring continuity over the weekend, including the earth straps/wires, and everything is in order.

I had a quick look last night at my wheel speed sensors for the front wheels for now but can only confirm that they are intact and have no breaks in the wires. From investigating, I see it is a fair effort in getting to the reluctor ring and will have to leave that upto my mechanic or Hyundai themselves (last resort).

My mechanic has one of those really expensive scanners (Autel I think), so I'll see if he can have a look for me as the scanner I have access to is one of those cheapies and interfaces with a mobile App.

[Picarro]

Did you mechanic find the error? I have the exact same problem on my 2017 i30 PDE with the 1.4 T-GDi, and my scanner also finds no problems.

[Gazza-75]

My mechanic is crazy busy, so he hasn't been able to look as yet. He mentioned that a friend (UK Hyundai mechanic) said badges can start to 'peel' and cause the radar to play up.
I don't think this is my issue as my badge is the smooth one piece badge and not the embossed badge.

I'll post again the second my mechanic has had a look.