Headlight Beam Bending AFS system Faults

[One Pot]

Hi ,  

My trusty superb has let me down at MOT time.  

The Headlight control module is able to communicate with the diagnostic computer, but it is reading the following faults

1537 - Sender for levelling supply voltage out of range

496 Sensor front vehicle level Open/Short circuit

497 Sensor rear vehicle level Open/Short circuit

 

When powering up the car, the headlights do not move in any way, and are set to illuminate the ground 4 feet in front of the car.

 

I struggle to believe that various wires have failed simultaneously, Do these symptoms indicate anything?  

 

thank you

 

Onepot

 

 

Edited 26 March, 2018 by One Pot
Clarity when re-reading

[langers2k]

Could be a failing AFS master as that provides power to the front and rear level sensors.

 

Not sure how you'd check apart from by replacing the AFS master as I don't know what voltage they expect.

[cssuk]

on my vehicles mot history since the first  one it has failed each year on headlight levels yet the AFS works perfectly is it in the Auto position as all other positions disable the AFS

[chimaera]

15 hours ago, cssuk said:

on my vehicles mot history since the first  one it has failed each year on headlight levels yet the AFS works perfectly is it in the Auto position as all other positions disable the AFS

Have you got a source for this?

 

I'm pretty certain AFS works regardless of the headlight position, since one of its functions is correcting beam aim when the suspension is loaded up. If you're experiencing different behaviour in auto vs manual control something is wrong with your car and you should have it checked over.

[cssuk]

The auto level is not AFS the OP stated no self test or movements took place when the lights were turned on this only happens when in auto page 51 of the owners manual.

A failure is indicated by the lights being in the lowest position so yes there may be a fault but try it in auto as well it may just need to reset in some way.

[chimaera]

Your version of the manual is a bit different to mine: AHL is on page 54 on the version I have (05/2012). In any case it seems you're right about AHL only working from the Auto position, which to me is unexpected behaviour given how useful the system is in any driving condition.

 

In any case, this warning may be relevant to the OP's problems (from page 57):

Quote

If the cornering lights are defective, the headlights are automatically lowered
to the emergency position, which prevents a possible dazzling of oncoming
traffic. Thus the illuminated length of the road is shortened. Drive carefully
and visit a specialist garage as soon as possible.

 

[cssuk]

sorry being a geek i read it on my phone the actual physical book is the same page

there is actually an option to turn off the AFS in the menu might be worth checking as well

Edited 27 March, 2018 by cssuk

[One Pot]

Quick update.  My "specialist" VW garage had no experience of the AFS.  My problem was that the AFS failure gave a non-MOT acceptable beam pattern.  The garage have mechanically adjusted the headlights to provide an acceptable pattern which means that I can now retrieve my car and get it investigated else where, but with an MOT!

 

I will update the eventual solution!

 

Cheers all

Onepot

[chimaera]

2 hours ago, One Pot said:

Quick update.  My "specialist" VW garage had no experience of the AFS.  My problem was that the AFS failure gave a non-MOT acceptable beam pattern.  The garage have mechanically adjusted the headlights to provide an acceptable pattern which means that I can now retrieve my car and get it investigated else where, but with an MOT!

 

I will update the eventual solution!

 

Cheers all

Onepot

If they're a VW specialist, they should have at the very least been able to connect diagnostics and check for fault codes, even if they had no experience dealing with AFS. Find a competent specialist next time.

[One Pot]

Hi Chimera, in fairness to the garage, they did diagnose the fault codes, (see first post) but were honest enough to say they had no experience, or specific training on the particular system.  Lights have been adjusted to meet the MOT requirements and I will now take some time to do a thorough investigation. 

[cssuk]

i dont get that as the AFS lights have no manual adjusters as far as am aware as it would make the whole AFS thing pointless, you have tried it in Auto and checked AFS is enabled in the settings?  normally you will get a dash error if the AFS is inop

[chimaera]

1 minute ago, cssuk said:

i dont get that as the AFS lights have no manual adjusters as far as am aware as it would make the whole AFS thing pointless, you have tried it in Auto and checked AFS is enabled in the settings?  normally you will get a dash error if the AFS is inop

There's a manual adjustment on the lamps but you have to put the system into 'Basic Settings' mode using diagnostics before aligning them with a beam setter. This sets the nominal position for the lamps, and the AFS controller moves them from there.

[langers2k]

8 hours ago, One Pot said:

Hi Chimera, in fairness to the garage, they did diagnose the fault codes, (see first post) but were honest enough to say they had no experience, or specific training on the particular system.  Lights have been adjusted to meet the MOT requirements and I will now take some time to do a thorough investigation. 

 

Hopefully they set the lights to the lowest level to pass the MOT?

 

As self-levelling isn't works (and should be an MOT fail) there is a good chance you will be causing glare under acceleration or with the rear of the car laiden. At the very least, I'd get them adjusted so they are 'too low' to avoid issues until it's fixed.

 

You should get a local member to do a full autoscan using VCDS, that'll confirm which AFS module you have and any related fault codes.

 

A used AFS master is £30-40 on eBay but will need coding after fitting and basic settings/headlight alignment doing. If the errors persist, you'll need to check the wiring: http://wiki.ross-tech.com/wiki/index.php/01537

[One Pot]

Thank you Langers2k, It will certainly get sorted.  

 

I also stumbled across this if it is of use to anyone!  VCDS Owners map

Edited 30 March, 2018 by One Pot
Adding VCDS owners map