Well done: clear photos and well explained. [smiley=cheers.gif]

 

Very good, worth adding to the KB for sure.

 

Very good, worth adding to the KB for sure.

Added yesterday.

 

Very good, worth adding to the KB for sure.

Added yesterday.

Thanks for that post! I have been getting frequent empty reservoir warnings, but not sure if it's the pump or the reservoir. Is there anyway to find out? I've just been topping up with water whenever it shows, and it's quite intermittent. I don't use the washer much at all, so really not fussed if it's not fixed though...

 

Nice write up!

You can find this in the following workshop manual -

FAQ - Audi TT (8J) Workshop Manuals & Self Study Programs
2.1 Electrical System (A005TT01320)
https://www.ttforum.co.uk/forum/viewtop ... &t=1833829

The two separate circuits each have their own pump but both draw off the same reserviour; one for the headlight washer system and one for the windscreen washer system.

1. Headlight Washer System: https://audi.7zap.com/en/rdw/audi+tt+tt ... 55-955030/
2. Windscreen Washer System: https://audi.7zap.com/en/rdw/audi+tt+tt ... 55-955010/

 

For the headlight washer, the delay and activation times can be modified using a VCDS in 09-Cent. Elect.
Note - this is a pre-facelift 2007 so newer models may be different.

You can also do the long code change with OBDeleven or turn it off completely quite easily using their App -

 

Is the delay the length of time after pulling the stalk (for windscreen) that it activates the headlight washers?

What is the 'activation time'?

 

@ MT-V6 - I believe "delay" is how frequently the headlight washers go on (I think default is every 10th time you run the windshield washers with the headlights on). And "activation" is how long they pump washer fluid onto the headlights. If you un-tick Bit 1, that should completely deactivate them so they don't come on at all.

If you don't have a VCDS to change the programming, you can simply pull the fuse for the headlight washer pump as noted in this post -

Just Disabled my Headlight Washers
https://www.ttforum.co.uk/forum/viewtop ... 9&t=187757

One note of caution - before fully deactivating them, I would recommend flushing the headlight washer system with winter washer fluid so they don't freeze up and risk cracking the washer jet mechanism and/or the fluid hoses.

Also, for anyone in the UK, deactivating them may fail a MOT inspection. Evidently if headlight washers are OEM fitted, they're supposed to work. Check the latest MOT updates to be sure!

http://www.ukmot.com/manual/1.7/Headlamps#MOT

" Headlight washers on vehicles first used from 1 September 2009 (if they have them)"
Https://www.gov.uk/government/news/mot- ... 0-may-2018

 

Thanks for this, really helpful 8)

 

This is what I got with OBDeleven sitting at my desk looking at Control Unit → Central Electrics 09 → Long Coding.

Hopefully with the unit connected, you should be able to make the changes to Byte 5 headlight washer delay and Byte 6 Headlight washer activation times using the Adaptation feature. (Note - this is a pre-facelift Mk2 so this may be different for newer models)

 

Note that the coding differs on pre and post facelift cars (roughly - CECM vs BCM)

09-Cent. Elect

• CECM
  • Byte 1, bit 1 - enable 'Headlight Washer installed'
  • Byte 5, bits 0-7 - 'Headlight Washer Delay' (default: 20 x 50 = 1000ms)
  • Byte 6, bits 0-7 - 'Headlight Washer Activation Time' (default: 28 x 50 = 1400ms) (also in adaptation channel 04)
• BCM
  • Byte 20, bit 5 - enable 'Headlight Washer installed'
  • Adaptation:
    • Channel 26 - 'Headlight Washer Activation Delay' (default: 4)