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B1020 71 Rain Sensor Communication Failure is the code I get from Tech 2. Wipers only work intermittently every 15 seconds, they don't adjust to rain. Also, my automatic headlights aren't working (they use the rain sensor for ambient light detection, right?), as in they don't go on/off automatically anymore. The "AUTO" position on the headlight switch just turns them off, whereas before they would come on if it was dark.

So I swapped in a known good rain sensor but same thing. Any ideas?
 

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Anyone? I just tried a third good rain sensor and same problem, so I know it's not the sensor itself. Error is actually "Rain sensor circuit malfunction". ??? :confused:
 

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Anyone? I just tried a third good rain sensor and same problem, so I know it's not the sensor itself. Error is actually "Rain sensor circuit malfunction". ??? :confused:
I haven't ventured into the SAAB wiring diagrams but the next thing I'd do is find and clean the connectors in the wiring. By "clean" I mean unplug and re-plug a few times.

The fancy (pricey) Deoxit spray cleans electrical connections that really helps old connections and switches. A spritz works wonders.
 

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I haven't ventured into the SAAB wiring diagrams but the next thing I'd do is find and clean the connectors in the wiring. By "clean" I mean unplug and re-plug a few times.

The fancy (pricey) Deoxit spray cleans electrical connections that really helps old connections and switches. A spritz works wonders.
Well, I've definitely unplugged it several times so far. The car is an '09, so the wiring is newer. Nothing looks out of place on the connector or the rest of the harness up in the roof area. I checked the REC and all the corresponding pins are there and working as they should.

I'm really stumped on this one!
 

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Checked the pertinent fuse in at the REC, fuse is fine (also powers rearview mirror which is working fine). Used a multimeter to check the plug that goes into the rain sensor, it's getting 12V power.

What else can I try?
 

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I thought u reconfigured your light switches AUTO position to be off. When I did that I lost all AUTO function.
I chose the middle option, "low beam ALSO in position 0". My headlights would come on automatically, I actually really liked the feature. Especially starting the car at night and then having the headlights only come on after leaving park. But hasn't been working ever since the rain sensor stopped working :cry:
 

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OK and so I just tested our other car again, 2008 9-3. Upon turning on the automatic wipers, normal operation is to make 1 reference swipe and then stop (until it rains). My 2009 9-3 makes 2 reference swipes back to back, then wipes every 15 seconds even though there is no rain. My '09 used to behave the same way as the '08.

Tried swapping the rain sensor again with the one from the '08 but no luck. After I returned the rain sensor to the '08 everything still worked as it should.

Any more ideas guys? I might have to start entertaining taking it to the dealer...:eek:
 

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Where do the wires run from the sensor and are there any connectors along the way?
The sensor wires (3 of them in the plug) run up into the overhead roof/map light area. I took that apart today to check for loose wires but didn't see any. Everything looked normal.

From there the wires run to the rear electrical center (fuse block in trunk). Then the REC talks to the I-BUS and tells the wipers what to do depending on the input from the sensor.
 

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The sensor wires (3 of them in the plug) run up into the overhead roof/map light area. I took that apart today to check for loose wires but didn't see any. Everything looked normal.

From there the wires run to the rear electrical center (fuse block in trunk). Then the REC talks to the I-BUS and tells the wipers what to do depending on the input from the sensor.
Its so ridiculous that the wires run all the way to the REC when the dash fuse panel is closer. Lol. Anyhoo, did u try to calibrate the rain sensor with the Tech2 through diagnostics/activations?
 

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Its so ridiculous that the wires run all the way to the REC when the dash fuse panel is closer. Lol. Anyhoo, did u try to calibrate the rain sensor with the Tech2 through diagnostics/activations?
Yeah I know :roll:. But I checked the pinouts and the wire colors match so they definitely run to the back.

I wasn't aware that you could calibrate the rain sensor via Tech 2. Did I miss something?
 

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Checked the wiring. The rain sensor wiring is intact and free moving, all the way up to the small hole it goes into in the light cluster that takes it to the trunk area. All pins on the connector are intact and in place.

Tested continuity on all 3 wires of the rain sensor plug, all tests normal and no open circuits.

?
 

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Did u try to totally remove & re add it with the Tech2? Also hate to say it, possibly the wiper stalk or switch in the CIM. :(
I removed and added the REC, yes. The wiper stalk does nothing, it's just a piece of plastic. Only the non-auto wiper stalk has electronic pins. The rain sensor stalk is just plastic.

The switch is built into the CIM. I doubt it's the wiper switch inside the CIM because I'm able to turn the wipers on low/high and the "auto" icon shows up on the SID.
 

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I removed and added the REC, yes. The wiper stalk does nothing, it's just a piece of plastic. Only the non-auto wiper stalk has electronic pins. The rain sensor stalk is just plastic.

The switch is built into the CIM. I doubt it's the wiper switch inside the CIM because I'm able to turn the wipers on low/high and the "auto" icon shows up on the SID.
Maybe when playing with the Tech2 u accidentally told the car it has intermittent wipers and not rain sensing. That would make sense that they only wipe every so many seconds, because there is no thumb wheel on the stalk. And there would be no communication with the rain sensor cuz the car doesn't think it has one?? Just guessing here..After re adding the sensor did u pull the battery neg to reset the electronics?
 

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Maybe when playing with the Tech2 u accidentally told the car it has intermittent wipers and not rain sensing. That would make sense that they only wipe every so many seconds, because there is no thumb wheel on the stalk. And there would be no communication with the rain sensor cuz the car doesn't think it has one?? Just guessing here..After re adding the sensor did u pull the battery neg to reset the electronics?
Didn't pull the neg terminal, but I'll try that too. I've always been careful to make sure I'm telling the Tech 2 to use the right settings. I even tried to re-add the BCM, UEC, and REC yesterday with proper settings. Although I didn't hit "remove" first, maybe I'll try that today.

I appreciate the guesses, keep em coming! ;ol;
 

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Problem SOLVED

Not exactly sure what the problem was, but I fixed it. I simply removed and re-added a few modules back to the car (BCM, MIU, CIM, REC, and UEC). Everything works normally now. Thanks to all for the help!
 

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I am having exactly the same problem with my Turbo X - if this fixes it I will love you forever!!!

I've been metering out the cables, full integrity from REC H2 connector to the connector at the Rain sensor. Have swapped out the rain sensor with another from a 03 9-3 and the 03 continued to function. Was just about to rip out and swap the two REC's but first I will try adding and removing modules.

Standby....
 
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