SaabCentral Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
2,473 Posts
Discussion Starter #1
So I've had my windshield replaced (twice now) and both replacements don't work with the rain sensor (yes, it's the correct style of windshield). The windshield I had before that got a huge crack in it worked fine (PGW) and this one is (Fuyao) isn't working (replaced twice). Now I don't recall on the previous windshield, but I'm pretty sure there was no "gel" applied to the bracket or anything. My new windshield (both times) had an adhesive gel applied.
Does anyone know if there is supposed to be a gel? Doesn't the rain sensor just clip onto the bracket which is mounted to the windshield with no need for any gel, or glue or whatever they applied to it?
The symptoms are that when the rain sensing is activated, the wipers go twice, then rest for about 10 seconds, then go twice, and rest again for 10 seconds. It just repeats that cycle no matter what sensitivity you have it set to and no matter how much rain is coming down.
The shop stated that they will pay for yet another replacement if I can prove that the windshield is in fact the issue, so I need ya'lls help on this one!

Thanks in advance!
 

·
Registered
Joined
·
573 Posts
cc’d from Al’s Red Wagon post in 2008:

I didn't know that Saabs had this...

Looks like the "up" position of the wiper control stalk is automatic for you. Try moving it down one click to take it out of auto mode.

For those of us without a rain sensor, that "up" position is intermittant. The next one is off, further down is slow, then the all the way down position is high.

The fault diagnosis in WIS says to make sure that your sensor is fastened well enough to the windscreen. This will help if you want to fiddle with it. What happens if you try that up position with the rain sensor detached?
 

·
Registered
Joined
·
2,473 Posts
Discussion Starter #3
If the sensor is unplugged, nothing happens, the wipers don't move since there's no signal. With it detached, they swipe once like they should. When mounted to the windshield they swipe twice because the sensor can't see properly (in layman's terms). That's why I'd like to know if there actually should be a gel/glue/adhesive on it because that might be the actual problem.
 

·
Registered
Joined
·
573 Posts
Examine the gel from the glass side. In a prior post on this subject someone said that there has to be absolutely no bubbles in the gel in order for the sensor to work properly.
 

·
Registered
Joined
·
2,473 Posts
Discussion Starter #5
Examine the gel from the glass side. In a prior post on this subject someone said that there has to be absolutely no bubbles in the gel in order for the sensor to work properly.
I guess this is the issue then.
275142
 

·
Registered
Joined
·
7,666 Posts
Rain sensor needs gel pad, otherwise IR spreads too much and wipers do not work as they should.
Rain sensor uses IR to check rain drops in windshield.
 

·
Registered
Joined
·
1,087 Posts
Is it practical to re-use a sensor pulled from a windscreen? Can the gel pad be bought separately, and whats the procedure for successful attachment?
 

·
Registered
Joined
·
7,666 Posts
You can re-use rain sensor. Only when gel pad or rain sensor itself is broken, you need to replace it.
ORIO (Saab) do not offer gel pad separately.
Original rain sensor is Bosch.
 

·
Registered
Joined
·
1,087 Posts
There was a thread on uksaabs which put the blame on the re-attached rain sensor not being aligned with a the hole in the black part of the screen glass. Its visible in your pic, far side of the sensor gel, 4 mm across. The sensor on the PCB has to be able to see through it, and it's easy to misalign. Not sure how you would align it if the bracket wasn't already bonded to the screen.
 

·
Registered
Joined
·
2,473 Posts
Discussion Starter #10
There was a thread on uksaabs which put the blame on the re-attached rain sensor not being aligned with a the hole in the black part of the screen glass. Its visible in your pic, far side of the sensor gel, 4 mm across. The sensor on the PCB has to be able to see through it, and it's easy to misalign. Not sure how you would align it if the bracket wasn't already bonded to the screen.
I mentioned misalignment and of course "we triple checked, it's 100% lined up".
 

·
Registered
Joined
·
8,895 Posts
Unfortunately rain sensor has no Tech II communication or diagnostics.

What I can try later is to cover my rain sensor with something opaque, and see if the wipers follow the same pattern as yours. If they do, the sensor isn't seeing any change from the test wipes and is trying over and over again. If my system behaves differently, well WIS doesn't seem to cover rain sensor malfunctions very well.
 

·
Registered
Joined
·
2,473 Posts
Discussion Starter #12
Unfortunately rain sensor has no Tech II communication or diagnostics.

What I can try later is to cover my rain sensor with something opaque, and see if the wipers follow the same pattern as yours. If they do, the sensor isn't seeing any change from the test wipes and is trying over and over again. If my system behaves differently, well WIS doesn't seem to cover rain sensor malfunctions very well.
I'd appreciate it Ed. Thanks in advance!
 

·
Registered
Joined
·
1,191 Posts
Distance between the sensor and glass is critical. Have someone spray a water mist on your windshield and with key on and the wiper on Auto setting gently push the sensor towards the glass. You may find the wiper speed to be fast and then slow as you lighten pressure on the sensor. If this is the case you’ll need to add a shim behind the side clips that hold the sensor in place. Alternatively, the bracket may be a loose fit against the glass - carefully, try putting a few drops of SuperGlue between the bracket and glass and holding the bracket tightly against the glass until it sets.
 
1 - 13 of 13 Posts
Top