[wonderings]

Not sure why you want want to only spray windshield washer fluid without the wipers going? Is there that much of a delay from when you hit it and when the fluid actually sprays? I have not used mine yet in my '13 OB.

 

[CNY_Dave]

When the windshield is really crudded up, you need to soak it before the wipers start moving or you are just grinding crud into the glass. Any delay is too much.

 

[wonderings]

When the windshield is really crudded up, you need to soak it before the wipers start moving or you are just grinding crud into the glass. Any delay is too much.

That I understand. I just make sure I scrape my windshield clean of ice rather then relying on my wipers to clean up the build up that can quickly accumulate when sitting. Been through enough wiper blades in other cars trying to use them without a clean windshield to not want to go through that anymore.

 

[plain OM]

Dave:

Appreciate what you're looking for but I'm not sure it can be done easily. The wiper/washer control is all in the combination switch, and incorporates an Intermittent Wiper Module (IWM) that is triggered by the washer switch to operate the wipers when the washer is activated.

I've attached the wiring diagram for the front system. The washer switch triggers the IWM when it connects the two lines (probably printed circuit traces) coming out of the top of the IWM rectangle. In this regard, normally there's 12 V between the two lines (and across the washer switch). When the switch is closed, I believe the drop across the two lines (goes from hi to low) causes the IWM to activate.

I would imagine that if the two lines going into the IWM are cut, the washer would work but the wipers would have to be turned on manually. However, even if the objective could be achieved, it might still be nice to retain the original functionality as well for those times when the window doesn't have to be drenched first, and at this stage this looks to be more of a challenge.

Maybe there's an easier way that I haven't thought of . . .

 

[CNY_Dave]

Hmmm, bet I could take the wiper switch assembly apart, but I'm (rarely) that ambitious.

I would never miss the auto-on feature, gone for good is good by me, but looks like I'll be reduced to wiring the washer motor to a separate switch (perhaps leaving the stock switch connected and isolating them with a diode).

Crap-o-la.

 

[Timberwolf99]

Try this link, thanx to Phizinza for the article.

Outback Windscreen, Spray then Wipe! - OffroadingSubarus.com

 

[CNY_Dave]

Excellent, thanks!

I was hoping to find an easy-to-cut-trace, an easy-to-remove 0-ohm resistor is even easier!

 

[plain OM]

That's a great photo.

I was hoping to find an easy-to-cut-trace, an easy-to-remove 0-ohm resistor is even easier!

Looks like "103" on the resistor, so 10k Ohms, but I think the idea is the same -- you're opening one of the lines that connects the washer switch to the IWM circuit (the transistor at the lower right).

Let us know how/if it works. (Wonder if the 2005+ is the same.)

 

[CNY_Dave]

I didn't look close, assumed they used a resistor just as a bridge, but it's used as a sense input which sees the +12V at the 'ground' side of the washer motor get pulled to ground.

Lucky that it doesn't have to get pulled to +12V on the module side.

 

[Euchre]

What would be really smart is if the wipers didn't start until you released the switch. Then, for those times when you just need to mist and wipe, you'd just tap the switch; heavier gunk hold until its wet enough.

But what do I know, I just drive cars. I is not an engineer.
(Pssst, are you looking Subaru?)

 

[plain OM]

but it's used as a sense input which sees the +12V at the 'ground' side of the washer motor get pulled to ground.

Yes, looks that way.

 

[CNY_Dave]

What would be really smart is if the wipers didn't start until you released the switch. Then, for those times when you just need to mist and wipe, you'd just tap the switch; heavier gunk hold until its wet enough.

But what do I know, I just drive cars. I is not an engineer.
(Pssst, are you looking Subaru?)

That would be great except when it's frozen or empty... I've used good schmutz but still have had it freeze in the lines below -10F, usually after a 'warm' spell.

 

[CNY_Dave]

Below, photo from the article:

Well, crap, mine is different from that.

Looks like that one had the wiper on the left side of the column, mine is on the right, as my board looks a little like a mirror-image of that one but the layout is also different.

I think I have the correct resistor isolated, stalk connector looks different.

 

[CNY_Dave]

Success!

I cut the track instead of removing the resistor.

 

[rasterman]

Congrats! Your pictures didn't work though.

 

[CNY_Dave]

Hmm, they are in place and visible for me.

I'll upload direct to this site...

 

[plain OM]

Great!

Also, good close up photos. Looks as if that resistor might be marked "183", which would be 18k Ohms, but no matter, the mod works as you want it to.

 

[CNY_Dave]

If you look close and squint, the resistor in the original mod pic looks to be 183 as well, in logic circuit design it's used as a 'pull-down' resistor, coupling the washer-motor lead to the intermittent controller; voltage on that pin gets pulled down to GND when the washer button is pushed.

The washer mnotor gets +12V, then the 'gnd' side goes to the washer button, it floats at +12V when the washer button is not pushed.