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  #1  
Old 04-07-2003, 01:27 PM
mechmagcn's Avatar
Just another diesel junky
 
Join Date: Aug 2002
Location: Mt Holly AR
Posts: 290
Angry 300SD central locking system has a mind of it's own!

I've never seen this one discussed before. When I lock the driver's door, the other doors lock like they are supposed to. Then they unlock, then they lock again and continue to cycle like this until I unlock the driver's door.
Someone please help!!!!
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1971 R600 Mack toterhome (SuperDawg)
99 NU-WA Snowbird 34+2 SE 102 5er
If it's not diesel, it's not in my stable!
53 F100 617.951/auto
95 Dodge 3500 Cummins/5 speed service truck
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  #2  
Old 04-07-2003, 04:03 PM
sixto's Avatar
smoke gets in your eyes
 
Join Date: Jun 2000
Location: SF Bay Area
Posts: 20,787
Sounds like a bad lock switch in the driver's door handle. I don't think they can be cleaned or repaired.

Sixto
91 300SE
87 300SDL
83 300SD
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  #3  
Old 04-07-2003, 09:08 PM
mechmagcn's Avatar
Just another diesel junky
 
Join Date: Aug 2002
Location: Mt Holly AR
Posts: 290
Angry AARRRRGGGHHHH!!!!!!!! Now it won't do it!!!!

Went out to check it out when the Ol' Lady got home. Everything works like it's supposed to.

Sixto, how could the switch cause this? Seems that the motor reverses and unlocked the doors. Then reversed again to lock. The driver door lock never moved.
Thanks, Jeff
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1971 R600 Mack toterhome (SuperDawg)
99 NU-WA Snowbird 34+2 SE 102 5er
If it's not diesel, it's not in my stable!
53 F100 617.951/auto
95 Dodge 3500 Cummins/5 speed service truck
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  #4  
Old 04-07-2003, 09:35 PM
Registered User
 
Join Date: May 2001
Location: Florida
Posts: 1,105
let me know if you find the problem, mine started doing similar stuff over a year ago and i just disconnected it. I dont think it could be the switch in the door. The switch in the door is very simple, there are three wires. When the switch is up it touches the "main wire" to the unlock wire that goes to the pump, and when it's locked it touches the "lock wire" to the main wire.
Ryan
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83 300SD.......sold
96 integra SE....sold
99 a4 quattro....sold
2001 IS300.......sold
2002 330i.........current.
2004 highlander limited....current.
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  #5  
Old 04-08-2003, 03:10 AM
sixto's Avatar
smoke gets in your eyes
 
Join Date: Jun 2000
Location: SF Bay Area
Posts: 20,787
I'll presume you're asking about the 81 SD in your sig line.

I don't know that it's a bad switch. I was just guessing that something was loose in the switch. I retract that guess.

The switch at the door does two things at the pump. First is to get it running (it only goes one way), the other is to connect the hose that goes to the lock actuators to the pressure side or vacuum side of the pump as needed. The act of locking or unlocking triggers actuators in the pump assembly to set the pump and hose to expect the next signal; lock if it just unlocked, unlock if it just locked.

I'll bet the 85mph speedo that shouldn't be in my 83 SD (reads only 110Kmiles) that the problem is a sequence pressure switch actuator stuck sending +12V to the pump when the door switch is in the lock position. That would send a constant +12V to the pump triggering a loop.

Could there be a keyless entry or aftermarket alarm system in the mix?

Sixto
91 300SE
87 300SDL
83 300SD

Last edited by sixto; 04-08-2003 at 03:19 AM.
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  #6  
Old 04-08-2003, 03:53 PM
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Join Date: May 2001
Location: Florida
Posts: 1,105
I beleive my problem is a bad pump, and these are expensive. That is why i havn't fixed it. I checked all doors/lines for leaks, and none were present. Also, on my 83 there isn't even a vacuum line running to the driver's side, as the driver's side lock is the only lock that activates the central locking system. I beleive on the 85 and up ones you can lock/unlock the entire car from the driver or passenger side, and the trunk. i could be mixed up on some of my info though. Hope this helps
Ryan
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83 300SD.......sold
96 integra SE....sold
99 a4 quattro....sold
2001 IS300.......sold
2002 330i.........current.
2004 highlander limited....current.
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