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Can someone please explain to me what the start bridge relay does?

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Can someone please explain to me what the start bridge relay does?

 
Old 12-11-2012, 08:45 PM
  #16  
Alan
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The sole purpose of the switch is to dissengage the cruise during gear changes - then it auto resumes - this features works very well - but is rather important on a manual car, lest the Bwaahh! becometh too much....

Apparently only the drivers of Rogerboxes need to be protected against themselves for inadvertent starter issues...

Alan

Last edited by Alan; 12-11-2012 at 09:10 PM.
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Old 12-12-2012, 01:50 AM
  #17  
James Bailey
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Originally Posted by Alan View Post
Apparently only the drivers of Rogerboxes need to be protected against themselves for inadvertent starter issues...

Alan
I rather like that
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Old 12-12-2012, 03:08 AM
  #18  
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Regarding starter bridge for manual cars: configuration changed for 1982 MY.
That bridge only exists in the CE panel of manual cars, MY 1981 and earlier.
(Alan is picturing a bridge in a late model panel, maybe his 94, for which purpose is a backup light bridge)

Mid year manual cars have a start bridge, but its located in the hatch area.
And, beginning 1982, both auto and manuals have the start relay.
See the first 2 documents below.


The confusion comes in when people with manual cars newer than 1981 go searching for the start bridge so solve a no-turnover issue and find a relay.

Its perpetuated because the manual start bridge is referenced in relay diagrams, including PET and 928specialist site, and has a part number. This co-location infers that the bridge located in CE panel.
But they are talking about two different configurations of bridge.

82-on manual owners should find a relay in the slot. And the bridge is a wire jumper near where tranny harness attaches in hatch area. If automatic, instead of the jumper, there is a shift linkage position switch ensuring car will only start in P or N.

See the third document below.
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Last edited by Landseer; 12-12-2012 at 06:01 AM.
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Old 12-12-2012, 10:03 AM
  #19  
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I never did understand why this interlock was put into place for "safety". Starting an automatic car in gear is much less dangerous than starting a manual car in gear, with the torque converter not being direct drive with the wheels when stationary.

Dan
'91 928GT S/C 475hp/460lb.ft
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Old 12-12-2012, 03:05 PM
  #20  
ledee416
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Originally Posted by dprantl View Post
I never did understand why this interlock was put into place for "safety". Starting an automatic car in gear is much less dangerous than starting a manual car in gear, with the torque converter not being direct drive with the wheels when stationary.

Dan
'91 928GT S/C 475hp/460lb.ft
unless of course someone is standing in front of it
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Old 05-18-2015, 02:40 AM
  #21  
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Default Need a little help with starter bridge issue

First...I have an 82 928 S (manual). From what I have read from the previous posts is that my 928 has both the relay(XIV) and a bridge (somewhere in the spare wheel well). Is this correct?

I ordered the Relay referencing the wiring diagram and part numbers from Porsche International..According to this wiring diagram Relay XIV for 82-84 model years has part no. 92861247300(Bridge for Starter-M/T). I ordered the part but it is not a relay. I have included a picture. I am assuming that this is for the bridge in the sparewheel well.


Ok...I have two questions - 1) What is the part no for the relay that goes in the relay XIV spot? And 2) Can someone point me to a picture or explain where I can find the bridge in the spare wheel well? I dont see it, and have no idea where else it could be.

Thanks.
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Old 05-18-2015, 10:46 AM
  #22  
Alan
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You can use a standard 53B relay from Roger (etc) for any starter relay (even the early model start DISABLE relays) - or in fact you can use any standard Bosch SPST or SPDT relay (but get a reputable brand).

The bridge goes behind the plastic cover in the spare wheel well - above the battery box and ahead (in the car) of the spare wheel. many have never realized its there until directed to it - there may be a 'felt' like cover over it. You most likely already have a similar bridge installed there.

Alan
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