Pitch-sensor..where is it, and what does it do?

[bbig119]

While the car was in the shop for the clutch, I asked them to investigate why my keyless entry/alarm wasn't working.

They hooked the car up to their computer, and came back a little puzzled. Without looking too much into it, the best they could do for me is hand over a couple printouts of faults that point to the pitch-sensor.

The guy at the shop told me that he's never had to touch this thing, and found out that its supposedly located somewhere in the trunk of the car by the wheel well. Instead of leaving the car there longer and being charged $80 an hour labor to have them go hunting, I opted to try and figure some of this out myself.

Specifically, the faults are as follows:

"16 Control wire, pitch sensor

Fault type:
Short circuit to the B+ or B- detected at the "pitch-sensor control wire" to the pitch sensor or the ultrasonic control unit

The fault has occurred 7 times so far"

The other one:

"6 Pitch Sensor

Fault type:
When the DWA is activated, the pitch sensor transmits no or a faulty asknowledgement signal to the DWA control unit.

The fault has occurred 87 times so far"


Can anyone help on this?

Thanks

[bbig119]

http://www.realoem.com/bmw/showparts.do?model=HE63&mospid=47410&btnr=65_1028& hg=65&fg=60

Well I'm not sure this is it or not, but it sounds like it could be-- inclination sensor. Also, for what its worth the cost is about the same as what the shop told me it lists for at the dealer.

Now, does anyone know anything about this thing and how I can get at it before I tear apart my trunk looking for it?

[632 Regal]

i have no fuc_ing clue, check all the wiring at the trunk hinge, those are usually frayed and give all sorts of failore messages. after that check the wiring from the battery to the under seat fuse board, pay particular attention to the wires and condition.

[ryan roopnarine]

a pitch/inclination/tilt sensor is there so that if you activate your alarm, and somebody loads your car on to a towtruck (tilting it), it won't be able to start until you deactivate it. makes sense that your alarm wouldn't work if it is defective. can you still operate the vehicle? is your keyless system a stock bmw one? i have no idea where it might be, but these questions will help others here.

[bbig119]

I've got the stock system on a 9/93 production 540. Given this and other threads on keyless entry stuff, it appers as though I've got EWS I. The first month I had the car(May) the keyless/alarm system worked sporadically for about a month, then in early June it quit working altogether- fortunately for me the alarm was not armed.

So I am able to drive the car just fine, but for all the keyless entry threads on this board, very little is info is out there about EWS I(maybe because it had a short production period).

I'll go looking for this pitch/tilt/incline sensor or whatever it is on Saturday.

[bbig119]

Can anyone with an ETK get me any additional info on this? I think I've found the "inclination sensor" as labeled in the realoem link above. I'm still not 100% sure its the same as the "pitch-sensor", but its my running theory. Its hard to see back there and if someone has a diagram of what else related to the alarm is back there it would be a great help. thanks.

[bbig119]

Ok, took something that looks suspect out, can you tell me what you think it is? My first concern is that the part number doesn't match up with what I saw in realoem.

This thing was located just in front of the factory amp, closer to the wheel well. the plug had only three wires go into it, and where they plug in(image 2), the contact are worn and could use a cleaning. Also, this thing when I shake it, there is definitely some liquid in it. I'm tempted to open it up, but could it be possible that the tilt/pitch sensor uses a liquid based mechanism for detection?

Here are images.








Edit: I just got off the phone with the stealership after talking to one not-so-helpful kid about this thing. What he did tell me is that apparently there are three part numbers for this thing, he made it seem like different revisions. The one on realoem is the correct/current part number and the one I have is obviously outdated. They quoted me $150 for a new one, but I'm not quite ready to jump in on that yet. I want to find out if it could just be cruddy contacts or maybe get a cheaper price from somewhere else first.

[632 Regal]

call or email BMA, they are more helpful than the stealer.

[bbig119]

I called and spoke with Patrick at BMA, he was friendly but didn't know much about this thing either. I called a buddy who is going to look into it and see if he can get a hold of one for me to try, otherwise I may just bite the bullet and buy a new one to see if it works.

I'm not sure if that will magically make it work though. The system has clearly locked itself down, it may need to be reset after replacement.