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Discussion Starter #1
All,

Does anyone know what the various components are on the PSE board?
I suspect the one component is an accelerometer but I could be wrong.

As with others, I have trouble with my board. Mine shows up as door locks that cycle up and down to the point of making me want to disconnect something.

I have taken the unit apart and cleaned it with advice I have gotten on this very site. Thanks for that.

There is no apparent damage, dirt, water, or degradation.

The door lock issue is generally preceeded by a thump from the trunk. I can't tell if it's from the module itself or from the trunk lock. It sounds more centered and not off to the side, so the location seems to be consistent with the trunk latch.

If the top is down, there is no lock problem. The locks act fine no matter what I do.

In stop and start driving situations, the locks will cycle when I corner, hit a bump, stop, slow, or accelerate but the actual precursor changes constantly. Meaning, sometimes it's fine but the locks go back up only when I corner. Other times only when I hit a bump. And so forth.

There is one component on the board that appears to have two white nylon adjustment wheels threaded onto a small shaft around a reed switch. I was thinking that was a motion sensor/accererometer and tried to adjust the play, or lack thereof, using the nylon wheels. I didn't seem to get much change from that so I haven't done anything other than to put it back the way I found it.

If anyone has figured out similar issues, I would be grateful for the answers.
My email address is [email protected] if that's easier.

Thanks in advance.

Mark
 

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I really have no idea what is in the PSE control unit, but it's function is to produce both pneumatic pressure and vacuum to power the door locks, etc. So it will certainly contain a motor.

There can be no use for an accelerometer in there, surely?
 

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Discussion Starter #3
Hard to say.

The alarm might have a motion sensor input and many cars have an accelerometer to deactivate the fuel pump or call for help.

That's another thing, now that I think of it. Twice, while driving, an alarm has gone off. It turns the radio screen off and seems to be calling for help.

Not sure what that was about.

Thanks,

Mark
 

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Your R170 has a crash shut-off relay located in the engine bay. This effectively isolates the battery in the event of a crash. It is initiated from the airbag triggering unit when the airbag is actuated. So the PSE system is not involved here. :)

The only acceleration sensor I can see is part of the brake system - 'ESP lateral acceleration sensor', located behind the gearshift lever.

How about this page from the WIS?

Problem: - Anti-theft alarm comes on while driving
Cause: - Trunk lock element out of adjustment causing central locking system to actuate and arming ATA. Stepping on brake pedal, or turning on ignition switch sets off alarm. (if stationary, presumably:confused:)
Remedy: - Adjust trunk lock element properly.
 

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Does the interior dome light comes on when this happens? In that case it may be that one of your doors does not push down enough on the door light switch. Close and lock the doors and push hard on each door from the inside.
I also like what Keyhole has published regarding the trunk lock.
 
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