BartmanEH

In my Canadian model TL, the headlight washers come on automatically whenever the headlights are on and you use the windshield washer. It's annoying because it activates the headlight washer and just as you finish wiping/washing the windscreen, it automatically does a follow up headlight wash and this oversprays all over the freshly wiped windscreen.

I would prefer to have the headlight washer completely under my own control using the headlight washer switch (next to the VSA OFF switch).

I've been thinking about modifying the wiring and have an initial idea I thought I'd throw out there to see what other electrical smarty pantses thought.

Here's the mod idea:


Here's how it would work: the headlight washer is controlled by a relay. The relay is controlled by the MICU. The MICU fires off the headlight washer relay whenever the headlight washer switch is activated OR whenever the MICU determines that both the headlights are on and the windshield washer is activated.

The headlight washer relay control line is a ground switch line controlled by the MICU. The headlight washer switch is also a ground switch line into the MICU.

If we disconnect the headlight washer relay control signal wire and the headlight washer switch signal wire from the MICU and simply connect them together, the MICU wouldn'y be able to turn on the headlight washer BUT the headlight washer can still be manually activated with the headlight washer switch.

Should work great. Thoughts?

potmilkz

can you just disable it? i dont see the point of having that function anyways.. the US specs are running just fine without it..

BartmanEH

Sure, I could just pull the 30A fuse for the headlight washer but what's the fun in that? I've got 'em and they can be useful just not in the idiotic way Acura decided to implement them. The auto headlight wash is stupid but a manual only headlight washer is the bomb!

BartmanEH

I tried to do this mod as indicated in the schematic proposed in my first post, however, after several hours gaining access to the connector on the passenger side MICU, I could not - for the life of me - remove the pins from the connector. I tried all manner of wires, pins, dental tools, miniature and jewelers screwdrivers - nothing would free the pins from the connector. I didn't want to cut any wires so I could return to stock if needed for warranty etc.

So I turned to the headlight washer switch and relay. I pull the relay from its holder and extended all the wires except the control signal wire. For that I connected a new wire from the relay control signal up to the headlight washer switch and tapped it in to the switch.

Works perfectly. Headlight washers are no longer controlled by the MICU - which decides to involuntarily turn on the headlight washers whenever the headlights are on and you use the windshield washer for the first time after turning on the lights.

Now the headlight washer only comes on when I press the headlight washer button. No more extra glycol being sprayed up on my hood. Even more annoying was the 2nd timed burst of headlight washer the MICU would launch after having finished wiping the windshield.

Here's the schematic of what I did:


Here's the relay rewired:


Here's the interception of the headlight washer switch signal:


To return to stock, I just need to pull the relay extension wires and put the relay back directly into its holder which has the original MICU based relay control signal.

potmilkz

so in what situation will you use these headlight washers?

sockpuppet

Just for clarity, the headlight washers will only triger with the windshield wash the first time you trigger it after turning the car on. And then, only if the headlights are on.
If the headlights are off (so, for instance, the daytime running lights are still on), then the headlight washer would not activate along with the windshield spray. Subsequent windshield sprays will not trigger the headlights spray.

The “extra” spray (after your windshield is already clean) can be cleaned by just pressing up on the wash lever.

I can see it as being an annoyance at times, however in this climate, I’m thankful for it. I would never re-wire to change it, but to each his own.

BartmanEH

For 4 months of the year I barrel down the highway in slushy conditions as part of my daily commute. It's nice to be able to wash the headlights to clear the caked and dried on salt and dirt.

It's feature on most high end European cars - North America is always slow to implement advanced features available for years overseas. e.g. auto-leveling or in-car adjustable HID beam height - required in Europe, not even available in North America. When your car is heavily loaded, it tilts the car upwards causing the HIDs to glare into oncoming traffic and causing the beams to be higher than optimal for the driver too.

I like my headlight washers and I use them regularly. I just wanted them under my control, not Acuras :-) I don't like Acura throwing extra washer fluid all over the hood of my car if I don't need it.

BartmanEH

...It's very odd of Acura to make this automatic link when almost nothing else is automatic in our cars (besides an auto headlight mode of dubious design where the HID headlights are on during starting and flickering as a result). There's no other auto features like triple flash for passing, auto leveling HIDs, etc. Why this silly linking of headlight washers the first time using the windshield washer when the headlights are on?

There are several other threads with people complaining about this "feature". The reason I started this thread was so that anyone wanting to change it could easily search and find the information on how I changed it. How about some more "thanks for the info" and less "why would you do this"? I'm looking for a pat on the back really, just hope someone else might find this information useful.

Teddybear

Thanks!! Now i gotta find somebody to help me with this. lol
In europe, it's mandatory for any car fitted with HID's to have a headlight washer.
I never understood why Acura made ours automatic. Drives me nuts!! Not to mention i have to refill the thing so often in the winter!

terdonal

Good work, it used to bother me on my ZDX as well. It should have been s separate switch in the first place.

sympley

Thanks for the DIY. I find it annoying as well when the thing pops out to wash the lights. In my Jetta I could hear the washers pop out and the pump working quite hard to spray, in the acura it seem very effortless and I always get caught by surprise. All I see mist and windshield washing fluid all over the front etc.

canuckshawd

so as potmilkz infers the american models do not have this feature.
coulldn't you just swap your relay for an american model?

09tl3.7

I noticed that every time I wash my windscreen the headlights spray twice but it's ok cause us Canadians have a larger washer reservoir anyways. Better to have then to need in these cases.

BartmanEH

Seems that my flickr image locations have gone invalid. Thought I'd repost the information here in case someone needs it.

Here's the schematic of the modification to disable the Acura computer's control of the headlight washer but keep manual control using the dashboard switch:


Here's a photo of how I implemented it. I removed the relay and wired up the relay with my own harness adapter thus allowing me to connect the relay control lead directly to the switch thereby bypassing the controller:

Madnesss

Can you post a picture of the wires you added in (when you removed the relay) to control the headlight washers by the headlight washer button only? (Not by the wiper switch) it says file has been removed.

csmeance

Also if you let off the brake with the wipers on while at a standstill, wipers will wipe as if you are anticipating to go forward and need a clear windshield.

BartmanEH

Why do these links always get broken? I spend more time fixing media links in old posts than contributing new information!


Here's the schematic:

kevin86

Ok, so basically the "square" means extend the connection. And feed the yellow into where the white wire would go for the relay?

BartmanEH

Yes, that sounds correct. I tapped into the yellow wire right up at the headlamp washer switch.

Bobloblaws

Does anyone know where the fuse is just for straight up disabling this feature.

BartmanEH

It's shown in the schematic I posted albeit it kinda low resolution. Here's a blowup: