The car will not start. Here are the diagnostic things done so far:

Will not crank - with lights on trying to crank will not dim lights.

Probed terminal wire on firewall to left of brake reservior - no juice to middle wire when cranking.

Disconnected cable to NSS and jumped terminals #81 and #50 on cable; when ingnition switch moved to ON position (not start) starter engages and continues to run. Car starts but starter running.

Hope someone can help diagnose .. seems like ignition switch, not NSS or is this an alarm relay problem and if so what's the fix??

Thanks in advance for any/all help

Cheers

Jumpering wrong terminals on NSS
N and P jumper is #50 and 50R--- not 81
You are tapping into back-up lamp circuit..

I would look at the alarm interupt relay, K38 I think.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

K38 would be another suspect , but you want to jumper the NNS first.
The K38 circuit can be jumpered at its relay terminal 3 and 1 , but it is much easier/faster to just check for power at terminal 50 of NSS with the key turned to Start position.
12 V test lamp here indicates AT circuit [ K38 ] OK...
The power chain is Ign sw -to K38- to NSS - to starter sol.
To make it easy all around . if one checks the center wire on the firewall
as you have done , that is the starter sol end of the circuit . The other end is the NSS , ..so your jumper is the correct next step. .. but you just have the wrong jumper terminals and are feeding the starter circuit through the Back Lamp contacts of the sw.
That is why your starter keeps turning.
If no 12 v at 50 of NSS, than ign/sw or K38 are suspect....

Thanks Arthur .. did jump #50 - #50R (on my cable only 3 terminals are numbered .. 81, 81a and 50, so I assume 50r is the unnumbered one) .. no joy on starting, but did not check power to 50, which I will do next .. if no power, what is the diagnosis, fix?

Thanks Again

Tim

ok
80/81a are the back up lamp circuit.. different contacts/circuit , as this is a dual circuit switch..

So, the feed from the ign/k38 go to feed 50 at NSS .. from there, power goes to 50r when in N or P [ through NSS contacts] and that feeds that center terminal I mentioned on firewall.
[ PS . for anyone ..the firewall terminal is another easy to get to test point for checking the starter/solinoid ... if one just brings a wire from bat + to this terminal. the starter will turn. This is a good test circuit break-point for diagnosis as it eliminate all interior switches and wireing by getting direct feed to starter , saving the Tech muchooo time decideing starter part of circuit or NSS/K38 circuit.. there are a few of these terminal spots that are easily gotten to without tearing stuff apart . this is where schematics are priceless and the Best Feature of the CDs... ]

If power at 50 and none at firewall.. has to be NSS
If no power at 50 , has to be K38 or ign sw not feeding NSS at50

Just remember there will be NO power at test lamp until you turn key to start
position... [ making sure you have tranny in Park when doing ANY starter circuit test]
I assume you are jumping the wire connector ends and NOT the terminals at the NSS....

Thanks Arthur, I will trace it out this afternoon, too bad the car is in a parking lot 25 miles from home. Do you have any thoughts about the gages going dead and the ABS light coming on while driving prior to the no start problem?