Doors unlocking while driving?!?
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Joined: Dec 2005
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From: SoCal. Desert
'16 E350, gone: '03 c230k
Doors unlocking while driving?!?
Wierd stuff. It happenned twice last week on the same morning. I hadn't driven her for ~week and took her to work on Monday. I usually have to do some driving around for work on Mondays, and during the morning trips the doors all unlocked themselves at ~40 mph on two separate occasions. Did not happen again the rest of the week.
Has anyone run across this?
Has anyone run across this?
Thread Starter
MBWorld Fanatic!
Joined: Dec 2005
Posts: 1,055
Likes: 50
From: SoCal. Desert
'16 E350, gone: '03 c230k
Hmmm, I didn't know abou tthe impact sensor and unlocking all doors on an impact. Very cool (probably standard on all cars now?). I just bought me a OBD scanner, but haven't had a chance to plug it in yet. No pot holes or anything - smooth road, just cruising at ~40mph.
Glyn - would you be able to point me to the location of the sensor? I'd guess the trunk based on samaritrey's post?
Edit: Just ran out and checked for codes - only thing I found was for the coolant level, which is the sensor (getting the same message on my cluster) I've had in hand since the 'coupons' and just haven't gotten around to replacing yet.
Glyn - would you be able to point me to the location of the sensor? I'd guess the trunk based on samaritrey's post?
Edit: Just ran out and checked for codes - only thing I found was for the coolant level, which is the sensor (getting the same message on my cluster) I've had in hand since the 'coupons' and just haven't gotten around to replacing yet.
Last edited by mtnman82; Nov 27, 2011 at 12:53 PM.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
No, the ESP, Yaw etc sensors are in the trunk. The impact sensor is behind the front valance somewhere IIRC. I will search for a diagram.
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Not in rear SAM 
For the rear SAM:
Relay Cavity
A Fuel Pump Relay
B Relay 2 Terminal 15R
C Reserve Relay 2
D Reserve Relay 1
E Rear Window Defroster
F Relay 1 Terminal 15R
G Filler Cap Relay Polarity Reverser 1
H Filler Cap Relay Polarity Reverser 2
For the rear SAM:
Relay Cavity
A Fuel Pump Relay
B Relay 2 Terminal 15R
C Reserve Relay 2
D Reserve Relay 1
E Rear Window Defroster
F Relay 1 Terminal 15R
G Filler Cap Relay Polarity Reverser 1
H Filler Cap Relay Polarity Reverser 2
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2006 C350 Sport 6MT
This happened to me couple of times. Once I hit a bad pothole and doors unlocked. Once I took a fast turn and heard a "boom" in the trunk and it unlocked the doors so I'm guessing something banged against the wall. Although it might also be a faulty sensor if it unlocks during normal driving
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Greg - I'm stumped at the moment unless in newer cars they use the ESP, Lateral accelerator sensor/Yaw sensors to pick this up now. It used to be near the temperature sniffer in older cars. See the ESP modules ahead of the spare wheel well below. It's not listed as a rear SAM module. Let me keep scratching - Maybe Trey can educate us or Russ can tell me why I'm confused regarding the rear SAM. I know the impact sensor was not a figment of my imagination on early cars. Belt tensioner & airbag sensor is in the center console area.
Last edited by Glyn M Ruck; Nov 27, 2011 at 05:55 PM.
MBWorld Fanatic!
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2006 C350 Sport 6MT
I think it has to do with the yaw sensor. The yaw sensor constantly measures for stability control so I have a feeling when this bad boy gets shocked it sends a signal and unlocks the doors. I don't think it's the rear sam but I could be wrong.
Thread Starter
MBWorld Fanatic!
Joined: Dec 2005
Posts: 1,055
Likes: 50
From: SoCal. Desert
'16 E350, gone: '03 c230k
Thanks for the info guys - I DO appreciate it! It hasn't happenned again since so I guess I'll just call it a fluke for now... If it does it again I'll be looking into the yaw sensors. You guys are awesome!
